Broadcast signal transmitting apparatus, broadcast signal receiving apparatus, and broadcast signal transceiving method in a broadcast signal transceiving apparatus

ABSTRACT

Disclosed is a broadcast signal transmitting apparatus, a broadcast signal receiving apparatus, and a broadcast signal transceiving method in a broadcast signal transceiving apparatus. The broadcast signal transmitting method comprises the following steps: compressing the headers of data packets of an IP stream identified by IP address information, wherein the compressed data packets include a first packet, the header of which contains static field information, a second packet, the header of which contains dynamic field information, and a third packet, the header of which contains the compressed static field information and/or the compressed dynamic field information; signaling IP-PLP mapping information for mapping the IP stream and a component PLP for transmitting the IP stream, the IP stream compression information, and the header information of the first packet to L2 signaling information; and transmitting the header information of the second and third packets via the component PLP, and transmitting the L2 signaling information via a common PLP.

This application is a continuation application of U.S. patentapplication Ser. No. 14/199,730 filed Mar. 6, 2014, now allowed, whichis a continuation of U.S. patent application Ser. No. 13/884,774 filedOct. 18, 2013, now U.S. Pat. No. 9,143,271, which is the National StageEntry of International Application No. PCT/KR2011/002284 filed Apr. 1,2011, which claims priority to U.S. Provisional Application No.61/319,880 filed Apr. 1, 2010, all of which are incorporated herein byreference in its entirety.

FIELD OF THE INVENTION

The present invention relates to a broadcast signal transmittingapparatus for transmitting a broadcast signal, a broadcast receivingapparatus for receiving a broadcast signal, and a method of transmittingand receiving a broadcast signal and, most particularly, to an apparatusand method for transmitting and receiving a mobile broadcast signal.

BACKGROUND ART

As the time has neared to end (or terminate) the transmission of analogbroadcast signals, diverse technologies for transmitting and receivingdigital broadcast signals are being researched and developed. Herein, adigital broadcast signal may include high capacity video/audio data ascompared to an analog broadcast signal, and, in addition to thevideo/audio data, the digital broadcast signal may also include diverseadditional data.

More specifically, a digital broadcasting system for digitalbroadcasting may provide HD (High Definition) level images,multiple-channel sound (or audio), and a wide range of additionalservices. However, a data transmission efficiency for transmitting highcapacity data, a robustness of transmitting and receiving network, andflexibility in a network considering mobile receiving equipments arestill required to be enhanced.

DETAILED DESCRIPTION OF THE INVENTION Technical Objects

Accordingly, an object of the present invention is to provide abroadcast signal transmitting apparatus and a broadcast receivingapparatus that can transmit and receive additional broadcast signals, amethod for transmitting and receiving additional broadcast signals, byusing an RE signal of a conventional broadcasting system without havingto ensure any additional frequency.

Another object is to provide a broadcast signal transmitting apparatusand a broadcast receiving apparatus that can transmit and receive mobilebroadcast signals, a method for transmitting and receiving mobilebroadcast signals, by using an RE signal of a conventional broadcastingsystem without having to ensure any additional frequency.

Yet another object of the present invention is to provide a broadcastingsignal transmitting apparatus, a broadcasting signal receivingapparatus, and a method for transmitting/receiving a broadcasting signalusing the same that can distinguish data corresponding to a service foreach component, and transmit the corresponding data to each componentthrough separate PLPs, so that the transmitted data can be received andprocessed.

Yet another object of the present invention is to provide a broadcastingsignal transmitting apparatus, a broadcasting signal receivingapparatus, and a method for transmitting/receiving a broadcasting signalusing the same that can signal signaling information required forservicing a broadcasting signal.

Yet another object of the present invention is to provide a broadcastingsignal transmitting apparatus, a broadcasting signal receivingapparatus, and a method for transmitting/receiving a broadcasting signalusing the same that can signal signaling information, so that abroadcasting signal can be received in accordance with a receivercharacteristic.

Yet another object of the present invention is to provide a broadcastingsignal transmitting apparatus, a broadcasting signal receivingapparatus, and a method for transmitting/receiving a broadcasting signalthat can reduce an overhead of a data packet by compressing a header ofthe data packet, when performing an IP-based transmission of abroadcasting signal, and transmitting the compressed header, and byhaving a receiver release the compression (or perform decompression).

Technical Solutions

In order to achieve the above-described technical object of the presentinvention, according to an embodiment of the present invention, abroadcasting signal transmitting method includes the steps ofcompressing each header of data packets included in an IP stream, the IPstream being identified by IP (Internet Protocol) address information,wherein the compressed data packets comprise a first packet having aheader including static field information, a second packet having aheader including dynamic field information, and a third packet having aheader including at least one of compressed static field information andcompressed dynamic field information, signaling IP-PLP mappinginformation for establishing a link between the IP stream and acomponent PLP (physical layer pipe) transmitting the IP stream,compression information of the IP stream, and header information of thefirst packet to L2 (Layer 2) signaling information, and transmittingheader information of the second and third packets through the componentPLP, and transmitting the L2 signaling information through a common PLP.

Effects of the Invention

According to the present invention, a transmitter may performtransmission by generating a PLP for each component configuring aservice, and a receiver may identify and decode the PLP, which isreceived for each component. Thus, the present invention may respond tothe mobile broadcast communication environment with more flexibility.

The transmitter of the present invention may distinguish one componentas a component of a base layer and as a component of at least oneenhancement layer, and may transmit the distinguished component. And,the receiver may decode only the component of the base layer so as toprovide an image with basic picture quality, or the receiver may decodethe component of the base layer along with the component of at least oneenhancement layer so as to provide an image with higher picture quality.Thus, the present invention may provide images having diverse picturequalities in accordance with the receiver characteristic.

By compressing a header of the data packet, when performing an IP-basedtransmission of a broadcasting signal, and transmitting the compressedheader, and by having the receiver recover the compressed header, thepresent invention may reduce the overhead of an IP-based data packet.Thus, IP-based broadcasting may be efficiently supported in a mobileenvironment.

By using a MIMO system, the present invention may increase datatransmission efficiency and may enhance robustness in broadcastingsignal transmission/reception.

Therefore, according to the present invention, the present invention mayprovide a method and apparatus for transmitting/receiving a broadcastingsignal that can receive a digital broadcasting signal without any erroreven in a mobile receiving equipment or an indoor environment.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates an exemplary super frame structure according to thepresent invention,

FIG. 2 illustrates an exemplary structure of a signal frame according toan embodiment of the present invention,

FIG. 3 illustrates a PLP-based signal frame structure according to anembodiment of the present invention,

(a) of FIG. 4 illustrates a P1 symbol structure according to the presentinvention,

(b) of FIG. 4 illustrates a block diagram showing an exemplary structureof a P1 symbol generator according to the present invention,

FIG. 5 illustrates an exemplary structure of a P1 symbol and anexemplary structure of an AP1 symbol according to an embodiment of thepresent invention,

FIG. 6 illustrates a block diagram showing a broadcasting signaltransmitting apparatus according to an embodiment of the presentinvention,

FIG. 7 illustrates a flow chart showing a method of transmitting aTS-based broadcast signal according to an embodiment of the presentinvention,

FIG. 8 illustrates a flow chart showing a method of transmitting aIP-based broadcast signal according to an embodiment of the presentinvention,

FIG. 9 illustrates a block diagram showing an input pre-processoraccording to an embodiment of the present invention,

(a) and (b) of FIG. 10 illustrate an example of configuring a PLP incomponent units in an input pre-processor according to the presentinvention,

(a) and (b) of FIG. 11 illustrate another example of configuring a PLPin component units in an input pre-processor according to the presentinvention,

FIG. 12 illustrates a flow chart showing a pre-processing method of abroadcasting signal according to an embodiment of the present invention,

FIG. 13 illustrates a block diagram showing an input pre-processoraccording to another embodiment of the present invention,

(a) and (b) of FIG. 14 illustrate another example of configuring a PLPin component units in an input pre-processor according to the presentinvention,

FIG. 15 illustrates a flow chart showing a pre-processing method of abroadcasting signal according to another embodiment of the presentinvention,

FIG. 16 illustrates a block diagram showing an input processor accordingto an embodiment of the present invention,

FIG. 17 illustrates a block diagram showing a mode adaptation module ofan input processor according to an embodiment of the present invention,

FIG. 18 illustrates a block diagram showing a stream adaptation moduleof an input processor according to an embodiment of the presentinvention,

FIG. 19 illustrates a block diagram showing a BICM module according toan embodiment of the present invention,

FIG. 20 illustrates a block diagram showing a frame builder according toan embodiment of the present invention,

FIG. 21 illustrates a block diagram showing an OFDM generator accordingto an embodiment of the present invention,

FIG. 22 illustrates a block diagram showing a BICM module according toanother embodiment of the present invention,

FIG. 23 illustrates a block diagram showing a frame builder according toanother embodiment of the present invention,

FIG. 24 illustrates a block diagram showing an OFDM generator accordingto another embodiment of the present invention,

FIG. 25 illustrates a data transmitting and receiving respective to anSM type MIMO transmission in a channel environment according to anexemplary embodiment of the present invention,

FIG. 26 illustrates a block diagram showing a broadcast signal receivingapparatus according to an embodiment of the present invention,

FIG. 27 illustrates a block diagram showing an OFDM demodulatoraccording to an embodiment of the present invention,

FIG. 28 illustrates a block diagram showing a P1 symbol detectoraccording to an embodiment of the present invention,

FIG. 29 illustrates a block diagram showing an AP1 symbol detectoraccording to an embodiment of the present invention,

FIG. 30 illustrates a block diagram showing a frame demapper accordingto an embodiment of the present invention,

FIG. 31 illustrates a block diagram showing a BICM decoder according toan embodiment of the present invention,

FIG. 32 illustrates a block diagram showing a OFDM demodulator accordingto an embodiment of the present invention,

FIG. 33 illustrates a block diagram showing a frame demapper accordingto another embodiment of the present invention,

FIG. 34 illustrates a block diagram showing a BICM decoder according toanother embodiment of the present invention,

FIG. 35 illustrates a block diagram showing an output processoraccording to an embodiment of the present invention,

FIG. 36 illustrates a block diagram showing an output processoraccording to another embodiment of the present invention,

FIG. 37 illustrates a block diagram showing a broadcasting signalreceiving apparatus according to another embodiment of the presentinvention,

FIG. 38 illustrates a block diagram showing a broadcasting signalreceiving apparatus according to another embodiment of the presentinvention,

FIG. 39 illustrates a block diagram showing the process of thebroadcasting signal receiver for receiving a PLP best fitting itspurpose according to an embodiment of the present invention,

FIG. 40 illustrates a MIMO transmission system and a broadcast signaltransmitting method using an SVC according to an embodiment of thepresent invention,

FIG. 41 illustrates a MIMO transmission system and a broadcast signaltransmitting method using an SVC according to other embodiment of thepresent invention,

FIG. 42 illustrates a MIMO transmission system and a broadcast signaltransmitting method using an SVC according to another embodiment of thepresent invention,

(a) to (c) of FIG. 43 illustrate a signal frame for transmitting data ofa base layer and an enhancement layer according to embodiments of thepresent invention,

FIG. 44 illustrates a block diagram showing a broadcasting signaltransmitting apparatus according to another embodiment of the presentinvention,

FIG. 45 illustrates a block diagram showing a broadcasting signalreceiving apparatus according to another embodiment of the presentinvention,

FIG. 46 illustrates an exemplary syntax structure of P1 signalinginformation according to an embodiment of the present invention,

FIG. 47 illustrates an exemplary syntax structure of AP1 signalinginformation according to an embodiment of the present invention,

FIG. 48 illustrates an exemplary syntax structure of L1-pre signalinginformation according to an embodiment of the present invention,

FIG. 49 illustrates an exemplary syntax structure of configurableL1-post signaling information according to an embodiment of the presentinvention,

FIG. 50 illustrates an exemplary syntax structure of dynamic L1-postsignaling information according to an embodiment of the presentinvention,

FIG. 51 illustrates a conceptual diagram of a correlation between aservice and a PLP group according to a first embodiment of the presentinvention,

FIG. 52 illustrates an exemplary syntax structure of a delivery systemdescriptor according to the first embodiment of the present invention,

FIG. 53 illustrates a flow chart showing the process steps of a servicescanning method of a receiver according to the first embodiment of thepresent invention,

FIG. 54 illustrates a conceptual diagram of a correlation between aservice and a PLP group according to a second embodiment of the presentinvention,

FIG. 55 illustrates an exemplary syntax structure of a component IDdescriptor according to the second embodiment of the present invention,

FIG. 56 illustrates a flow chart showing the process steps of a servicescanning method of a receiver according to the second embodiment of thepresent invention,

FIG. 57 illustrates a conceptual diagram of a correlation between aservice and a PLP group according to a third embodiment of the presentinvention,

FIG. 58 illustrates an exemplary syntax structure of a delivery systemdescriptor according to the third embodiment of the present invention,

FIG. 59 illustrates an exemplary syntax structure of a component IDdescriptor according to the third embodiment of the present invention,

FIG. 60 illustrates an exemplary PLP_PROFILE field according to thethird embodiment of the present invention,

FIG. 61 illustrates a flow chart showing the process steps of a servicescanning method of a receiver according to the third embodiment of thepresent invention,

FIG. 62 illustrates a conceptual diagram of a correlation between aservice and a PLP group according to a fourth embodiment of the presentinvention,

FIG. 63 illustrates an exemplary syntax structure of anIP/MAC_location_descriptor according to the fourth embodiment of thepresent invention,

FIG. 64 illustrates a flow chart showing the process steps of a servicescanning method of a receiver according to the fourth embodiment of thepresent invention,

FIG. 65 illustrates an IP header configuring of a header of a datapacket according to an embodiment of the present invention,

FIG. 66 illustrates a UDP header configuring of a header of a datapacket according to an embodiment of the present invention,

(a) and (b) of FIG. 67 illustrate a RoHC compression method according toan embodiment of the present invention,

FIG. 68 illustrates an example of IP-PLP mapping information andcompression information being signal to the IP information tableaccording to the present invention,

FIG. 69 illustrates a syntax structure providing a more detaileddescription of an IP/MAC_location_descriptor( ) shown in FIG. 68,

FIG. 70 illustrates another example of IP-PLP mapping information andcompression information being signal to the IP information tableaccording to the present invention,

FIG. 71 illustrates a syntax structure providing a more detaileddescription of an IP/MAC_location_descriptor( ) shown in FIG. 70,

FIG. 72 illustrates a block diagram showing a structure of a portion ofan input-pre-processor, which is used for compressing data packets,according to an embodiment of the present invention,

FIG. 73 illustrates a flow chart showing an input pre-processing methodincluding header compression according to the present invention,

FIG. 74 illustrates an example of merging header information of an IRpacket with a component PLP according to the present invention,

FIG. 75 illustrates another example of merging header information of anIR packet with a component PLP according to the present invention, and

FIG. 76 illustrates a block diagram showing a structure of abroadcasting signal receiving apparatus according to yet anotherembodiment of the present invention.

BEST MODE FOR CARRYING OUT THE PRESENT INVENTION

Reference will now be made in detail to the preferred embodiments of thepresent invention, examples of which are illustrated in the accompanyingdrawings. Wherever possible, the same reference numbers will be usedthroughout the drawings to refer to the same or like parts. And, thescope and spirit of the present invention will not be limited only tothe exemplary embodiments presented herein.

Although the terms used in the present invention are selected fromgenerally known and used terms, the detailed meanings of which aredescribed in relevant parts of the description herein. It should benoted that the terms used herein may vary depending upon the intentionsor general practice of anyone skilled in the art and also depending uponthe advent of a novel technology. Some of the terms mentioned in thedescription of the present invention have been selected by the applicantat his or her discretion, terms used herein. Furthermore, it is requiredthat the present invention is understood, not simply by the actual termsused but by the meaning of each term lying within.

The present invention relates to an apparatus and method fortransmitting and receiving an additional broadcast signal, while sharingan RF frequency band with related art broadcasting system, such as aconventional terrestrial broadcast system (or also referred to as a T2system), e.g., DVB-T2. In the present invention, the additionalbroadcast signal may correspond to an extension (or enhanced) broadcastsignal and/or a mobile broadcast signal.

In the description of the present invention, an additional broadcastsignal refers to as signal that is processed and transmitted inaccordance with a non-MIMO (Multi Input Multi Output) method or a MIMOmethod. Herein, a MISO (Multi Input Single Output) method, a SISO(Single Input Single Output) method, and so on, may correspond to thenon-MIMO method.

Hereinafter, 2 antennae may be given as an example of the multi antennaeof the MISO method or the MIMO for simplicity of the description of thepresent invention. And, such description of the present invention may beapplied to all types of systems using 2 or more antennae.

FIG. 1 illustrates an exemplary super frame structure including anadditional broadcast signal (e.g., mobile broadcast signal) according tothe present invention. A super frame may be configured of a plurality offrames, and the frames belonging to one super frame may be transmittedby using the same transmission method. The super frame according to theembodiment of the present invention may be configured of multiple T2frames (also referred to as a terrestrial broadcast frame) andadditional non-T2 frames for the additional broadcast signal. Herein, anon-T2 frame may include an FEF (Future Extension Frame) part beingprovided by the related art T2 system. The FEF part may not becontiguous and may be inserted in-between the T2 frames. The additionalbroadcast signal may be included in the T2 frame or FEF part, so as tobe transmitted.

When a mobile broadcast signal is transmitted through FET part, the FEFpart will be referred to as an NGH (Next Generation Handheld) frame.

At this point, 1 NGH frame may be transmitted for each N number of T2frames (i.e., NGH-T2 frame ratio=1/N or N:1), and the T2 frame and theNGH frame may be alternately transmitted (i.e., NGH-T2 frame ratio 1/2or 1:1). If the NGH-T2 frame ratio is equal to 1/N, the time consumed bythe receiver in order to receive an NGH frame after receiving a previousNGH frame is equivalent to the time corresponding to N number of T2frames.

Meanwhile, among the components configuring a broadcast service, thepresent invention may divide a video component to multiple videocomponents and may transmit the divided video components. For example, avideo component may be divided into a basic video component and anextension video component, and may then be transmitted accordingly.

According to an embodiment of the present invention, in order to enhancetransmission stability, the basic video component may be transmitted ina non-MIMO method, and the extension video component may be transmittedin an MIMO method in order to provide an enhanced throughput.

In the present invention, the basic video component will hereinafter bereferred to as a video component of a base layer, and the extensionvideo component will hereinafter be referred to as a video component ofan enhancement layer. Additionally, for simplicity of the description,in the present invention, the video component of the base layer will beused in combination with video data of the base layer (or data of thebase layer), and the video component of the enhancement layer will beused in combination with video data of the enhancement layer (or data ofthe enhancement layer).

According to an embodiment of the present invention, the presentinvention may encode video data by using an SVC (Scalable Video Coding)method, thereby dividing the encoded video data into video data of thebase layer (or base layer video data) and video data of the enhancementlayer (or enhancement layer video data). Herein, the SVC method ismerely exemplary. And, therefore, other arbitrary video coding methodshaving scalability may also be used herein.

The data of the base layer (or the base layer data) correspond to datafor images having basic picture quality. Herein, although the base layerdata are robust against the communication environment, the base layerdata have low picture quality. And, the data of the enhancement layer(or the enhancement layer data) correspond to additional data for imagesof higher picture quality and may, therefore, provide images having highpicture quality. However, the enhancement layer data are weak againstthe communication environment.

In the present invention, video data for terrestrial broadcasting may bedivided into base layer data and enhancement layer data, and video datafor mobile broadcasting may be divided into base layer data andenhancement layer data in order to flexibly respond to the mobilebroadcasting communication environment.

The receiver may decode only video layer of the base data (or base layervideo data), so as to provide an image having basic picture quality, orthe receiver may decode both the base layer video data and the videolayer of the enhancement data (or enhancement layer video data), so asto provide an image having a higher picture quality.

According to an embodiment of the present invention the enhancementlayer video data may be transmitted through an FEF, and the base layerdata may be transmitted through the T2 frame and/or FEF.

In the present invention, an audio component may include an audiocomponent of a base layer (or base layer audio component) for providingbasic sound quality, such as 2 channel or 2.1 channel, and an audiocomponent of an enhancement layer (or enhancement layer audio component)for providing additional sound quality, such as 5.1 channel orMPEG-Surround.

According to an embodiment of the present invention, a signal frame mayrefer to any one of a T2 frame, an FEF transmitting a mobilebroadcasting signal (i.e., NGH frame), a T2 frame transmitting baselayer video data, and an FEF transmitting enhancement layer video data.In the description of the present invention, the signal frame and thetransmission frame will be used to have the same meaning.

In the present invention, a PLP (physical layer pipe) corresponding toan identifiable data (or stream) unit. Also, the PLP may be consideredas a physical layer TDM (Time Division Multiplex) channel, whichtransmits (or delivers) one or more services. More specifically, eachservice may be transmitted and received through multiple RF channels.Herein, the PLP may represent a path through which such service is beingtransmitted or may represent a stream being transmitted through suchpath. The PLP may also be located in slots being distributed to multipleRF channels at predetermined time intervals, and the PLP may also bedistributed in a single RF channel at predetermined time intervals.Therefore, signal frame may transmit a PLP, which is distributed to asingle RF channel based upon a time reference. In other words, one PLPmay be distributed to a single RF channel or multiple RF channels basedupon a time reference.

In the present invention, one service may be transmitted to one PLP, andcomponents configuring a service may be divided (or differentiated), sothat each of the differentiated components can be transmitted to adifferent PLP. If service components configuring a single service aredifferentiated from one another so as to be respectively transmitted toa different PLP, the receiver may gather (or collect) the multiplecomponents, so as to combine the collected components to a singleservice. In the present invention, the service component and thecomponent will be used to have the same meaning.

FIG. 2 illustrates an exemplary structure of a signal frame over aphysical layer according to an embodiment of the present invention. Thesignal frame includes a P1 signaling information region (or part), an L1signaling information region, and a PLP region. More specifically, theP1 signaling information region may be allocated to a foremost portionof the corresponding signal frame, and, then, the L1 signalinginformation region and the PLP region may be sequentially allocatedafter the P1 signaling information region. In the description of thepresent invention, only the information being included in the L1signaling information region may be referred to as L1 signalinginformation, or signaling information being included in the P1 signalinginformation region and signaling information being included in the L1signaling information region may be collectively referred to as the L1signaling information.

As shown in FIG. 2, P1 signaling information that is being transmittedto the P1 signaling information region may be used for detecting asignal frame (or NGH broadcast signal) and may include tuninginformation and information for identifying preamble itself.

Based upon the P1 signaling information, the subsequent L1 signalinginformation region is decoded, so as to acquire information on the PLPstructure and the signal frame configuration. More specifically, the L1signaling information includes L1-pre-signaling information andL1-post-signaling information. Herein, the L1-pre-signaling informationincludes information required by the receiver to receive and decodeL1-post-signaling information. And, the L1-post-signaling informationincludes parameters required by the receiver for accessing the PLP. TheL1-post-signaling information may then include ConfigurableL1-post-signaling information, Dynamic L1-post-signaling information,Extension L1-post-signaling information, and CRC information, and theL1-post-signaling information may further include L1 padding data. Inthe present invention, configurable L1-post signaling information hasthe same meaning as the L1-post configurable signaling information.Moreover, dynamic L1-post signaling information has the same meaning asthe L1-post dynamic signaling information

Meanwhile, in the signal frame, the PLP region is configured of at leastone common PLP and at least one data PLP.

A common PLP includes PSI/SI (Program and System Information/SignalingInformation).

Specifically, when a broadcast signal is a TS format, the common PLP mayinclude network information, such as an NIT (Network Information Table),or PLP information, and service information, such as an SDT (ServiceDescription Table), an EIT (Event Information Table) and a PMT (ProgramMap Table)/a PAT (Program Association Table). Based upon the intentionsof the system designer, service information, such as SDT and PMT/PAT,may be included in data PLP and may then be transmitted. The PATcorresponds to special information being transmitted by a packet havinga PID of ‘0’, and the PAT includes PID information of the PMT and PIDinformation of the NIT. The PMT includes a program identificationnumber, PID information of a TS packet to which individual bit streams,such as video, audio, and so on, are being transmitted, wherein theindividual bit streams configure a program or (service), and PIDinformation through which a PCR is being delivered. The NIT includesinformation of an actual transmission network (i.e., physical network).The EIT includes information on an event (or program or service) (e.g.,title, start time, and so on). The SDT includes information describing aservice, such as a service name or service provider.

When a broadcasting signal corresponds to an IP format, the common PLPmay include an IP information table, such as n INT (IP/MAC notificationtable). In the description of the present invention information beingincluded in the common PLP may be referred to as L2 signalinginformation. In addition, the common PLP may further include startinformation such as bootstrap and meta data for service guide such asESG or SD&S.

More specifically, L1 signaling information includes informationrequired by the broadcasting signal receiver for processing a PLP withina signal frame, and the L2 signaling information includes informationthat can be commonly applied to multiple PLPs. Accordingly, thebroadcasting signal receiver may use P1 signaling information includedin a P1 signaling information region, so as to decode an L1 signalinginformation region, thereby acquiring information on the structure ofPLP included in the signal frame and information a frame structure. Mostparticularly, the broadcasting signal receiver may be capable of knowingthrough which PLP each of the service components being included in thecorresponding service is being transmitted by referring to the L1signaling information and/or the L2 signaling information. Additionally,the BICM module of the broadcasting signal transmitter may encodesignaling information associated with a broadcast service and maytransmit L1/L2 signaling information, so that the broadcasting signalreceiver can perform decoding. Moreover, the MICM decoder of thebroadcasting signal receiver may decode the L1/L2 signaling information.

At this point, when the L1 signaling information includes information onthe service components, the broadcasting signal receiver may recognizethe information on the service components at the same time thebroadcasting signal receiver receives the signal frame, and thebroadcasting signal receiver may then apply the correspondinginformation. However, since the size of the L1 signaling information islimited, the size (or amount) of the information on the servicecomponents that can be transmitted from the broadcasting signaltransmitter may also be limited. Accordingly, the L1 signalinginformation region is most adequate for recognizing the information onthe service components at the same time the broadcasting signal receiverreceives the signal frame and for transmitting information that can beapplied to the broadcasting signal receiver.

If the L2 signaling information includes information on the servicecomponents, the broadcasting signal receiver may acquire information onthe service components after the decoding of the L2 signalinginformation is completed. Therefore, the broadcasting signal receivermay not be capable of recognizing the information on the servicecomponents at the same time the broadcasting signal receiver receivesthe signal frame and may not be capable of modifying the correspondinginformation. However, since the size of the region transmitting the L2signaling information is larger than the L1 signaling informationregion, the L2 signaling information region may transmit a larger amount(or size) of service component data. Accordingly, the L2 signalinginformation is adequate for transmitting general information on servicecomponents.

According to an embodiment of the present invention the L1 signalinginformation may be used along with the L2 signaling information. Morespecifically, the L1 signaling information may include information thatcan be modified (or changed) at the same time the broadcasting signalreceiver receives the signal frame in a PLP level, such as a high mobileperformance and a high-speed data communication characteristic, or mayinclude information of service components that can be modified (orchanged) at any time during the broadcasting signal transmission.Additionally, the signaling information may include information on theservice components and general information on channel reception, whichare included in a service.

Meanwhile, if the broadcast signal corresponds to a TS format, a dataPLP, which is included in the signal frame, may include audio, video,and data TS streams. Furthermore, the TS-based data PLP may includePSI/SI information such as a PAT (Program Association Table) and a PMT(Program Map Table). If the broadcasting signal corresponds to an IPformat, the data PLP may include audio, video, and data IP streams. Atthis point, IP packets, which configure each of the IP streams, may bepacketized by using an RTP (Real Time Protocol) or FLUTE (File Deliveryover Unidirectional Transport). Additionally, IP-based data PLP mayinclude control information, which is packetized by using an RTSP (RealTime Streaming Protocol) method. In the present invention, a data ELFincluding PAT/PMT or a data PLP including control information may alsobe referred to a base PLP. The data PLP may include a Type1 data PLP,which is transmitted by one sub-slice for each signal frame, and a Type2data PLP, which is transmitted by multiple sub-slices. In thedescription of the present invention, for simplicity of the description,P number of data PLPs will hereinafter be indicated as PLP1˜PLPp. Morespecifically, audio, video, and data TS streams and PSI/SI information(or control information), such as PAT/PMT, are transmitted throughPLP1˜PLPp. The data PLPs of FIG. 2 correspond to examples afterscheduling and interleaving.

In the present invention the common PLP may be decoded along with a dataPLP, and the data PLP may be selectively (or optionally) decoded. Morespecifically, a common PLP+data PLP may always be decoded. However, insome cases data PLP1+data PLP2 may not be decoded. Information beingincluded in the common PLP may include the PSI/SI information.Additionally, Auxiliary Data may be added to the signal frame. Moreover,CRC data may be added to the signal frame.

FIG. 3 illustrates a signal frame structure at a symbol level accordingto an embodiment of the present invention.

In light of the symbol level, the signal frame according to the presentinvention is divided into a preamble region and a data region. Thepreamble region is configured of a P1 symbol and at least one or more P2symbols, and the data region is configured of a plurality of datasymbols.

Herein, the P1 symbol transmits P1 signaling information. The at leastone or more P2 symbols transmit L1-pre-signaling information,L1-post-signaling information, and signaling information being includedin the common PLP (i.e., L2 signaling information). The signalinginformation being included in the common PLP may be transmitted througha data symbol. Therefore, in light of the signal frame over a physicallayer, the preamble region includes a P1 signaling information region,an L1 signaling information region, and a portion or an entire portionof the common PLP region. In the description of the present invention aPLP transmitting PSI/SI and, more particularly, PAT/PMT will hereinafterbe referred to a base PLP.

Data PLPs being transmitted through multiple data symbols may include aType1 data PLP being transmitted, which is transmitted by one sub-slicefor each signal frame, and a Type2 data PLP, which is transmitted bymultiple sub-slices. According to an embodiment of the presentinvention, when both the Type 1 data PLP and the Type2 data PLP exist ina signal frame, the Type1 data PLP is first allocated, and the Type2data PLP is allocated afterwards.

The Type1 data PLP refers to having one sub-slice within a signal frame,i.e., one PLP being continuously transmitted within a signal frame. Forexample, when it is assumed that 2 type1 data PLPs (PLP1, PLP2) arebeing transmitted, when all of the data of PLP1 are first allocated tothe corresponding signal frame, then all of the data of PLP2 areallocated afterwards, and, thereafter, the data are transmitted.

The Type2 data PLP refers to a PLP having two or more sub-slices withinthe signal frame. More specifically, the data of each PLP are dividedinto as many sections as the number of sub-slices. And, then, thedivided data are distributed and transmitted to each sub-slice. Forexample, when it is assumed that 2 Type2 data PLP (PLP3, PLP4) exist ina single signal frame, and when it is assumed that each Type2 data PLPhas 2 sub-slices, the data of PLP3 and the data of PLP4 are each dividedinto 2 equal sections, and the divided data are sequentially allocatedto the 2 sub-slices of the corresponding PLP. At this point, accordingto the embodiment of the present invention, the sub-slice for PLP3 andthe sub-slice for PLP4 are alternately positioned so as to betransmitted accordingly. In order to gain higher time diversity, thepresent invention uses the Type2 data PLP.

In the description of the present invention, one data PLP may correspondto one service, and one data PLP may also correspond to any one of theservice components configuring a service, such as a video component (oralso referred to as a base layer video component), an extension videocomponent or also referred to as an enhancement layer video component),and audio component, and a data component other than the video and audiocomponents.

Meanwhile, the present invention may transmit separate signalinginformation from the transmitter, so that the receiver can identifyadditional broadcast signal frame, such as an NGH frame, and process theidentified frame. The present invention transmits separate signalinginformation through a P1 symbol. And, herein, the P1 symbol will bereferred to as a new_system_P1 symbol.

The new_system_P1 symbol may be different from the P1 symbol, and aplurality of new_system_P1 symbols may be used herein. At this point,according to the embodiment of the present invention, the new_system_P1symbol is located at the beginning of the signal frame, i.e., located ata front portion of a first P2 symbol within a preamble region. In thiscase, the preamble region may be configured of at least one or morenew_system_P1 symbols and at least one or more P2 symbols.

(a) of FIG. 4 illustrates a P1 symbol structure according to the presentinvention. In (a) of FIG. 4, the P1 symbol and P2 symbol portion will bereferred to as a preamble region, and a body region will be referred toas a data region. The data region may be configured of a plurality ofdata symbols (also referred to as data OFDM symbols).

In (a) of FIG. 4, P1 symbol is generated by having each of a frontportion and an end portion of an effective (or valid) symbol copied, byhaving a frequency shift performed as much as +f_(sh), and by having thefrequency-shifted copies respectively positioned at a front portion (C)and an end portion (B) of the effective symbol (A). In the presentinvention, the C portion will be referred to as a prefix, and the Bportion will be referred to as a postfix. More specifically, P1 symbolis configured of a prefix portion, an effective symbol portion, and apostfix portion. In the description of the present invention, such P1symbol structure will also be referred to as a C-A-B structure. At thispoint, according to the present invention, the P1 symbol corresponds to1K OFDM symbol. And, according to the embodiment of the presentinvention, the A portion (T_(P1A)) may have the length of 112 us, the Cportion (T_(P1C)) may have the length of 59 us, and the B portion(T_(P1B)) may have the length of 53 us.

(b) of FIG. 4 illustrates a block diagram showing an exemplary structureof a P1 symbol generator according to the present invention. Herein, (b)of FIG. 4 includes a CDS (Carrier Distribution Sequence) table module(000100), an MSS (Modulation Signaling Sequence) module (000200), aDBPSK (Differential Binary Phase Shift Keying) mapping module (000300),a scrambling module (000400), a padding module (000500), an IFFT module(000600), and a C-A-B structure module (000700). After being processedwith the operations of each block included in the P1 symbol generatorshown in (b) of FIG. 4, the P1 symbols shown in (a) of FIG. 4 is finallyoutputted from the C-A-B structure module (000700).

According to the embodiment of the present invention, the structure ofthe P1 symbol, shown in (a) of FIG. 4, may be modified, or the P1 symbolgenerator, shown in (b) of FIG. 4 may be modified, so as to generate anew_system_P1 symbol.

If the new_system_P1 symbol is generated by modifying the P1 symbolshown in (a) of FIG. 4, the new_system_P1 symbol may be generated byusing at least one of the following methods. For example, thenew_system_P1 symbol may be generated by modifying a frequency shift (ordisplacement) value (f_(SH)) for a prefix and a postfix. In anotherexample, the new_system_P1 symbol may be generated by modifying (orchanging) the length of the P1 symbol (e.g., T_(P1C) and T_(P1B)lengths). In yet another example, the new_system_P1 symbol may begenerated by replacing the length of the P1 symbol from 1K to512,256,128, and so on. In this case, the parameters (e.g., f_(SH),T_(P1C), T_(P1B)) that are used in the P1 symbol structure should beadequately corrected.

If the new_system_P1 symbol is generated by modifying the P1 symbolgenerator shown in (b) of FIG. 4, the new_system_P1 symbol may begenerated by using at least one of the following methods. For example,the new_system_P1 symbol may be generated by using a method of changingthe distribution of active carriers (e.g., a method of having the CDStable module (000100) use another CSS (Complementary Set of Sequence)),which are used for the P1 symbol, through the CDS table module (000100),the MSS module (000200), and the C-A-B structure module (000700). Inanother example, the new_system_P1 symbol may be generated by using amethod of changing a pattern for transmitting information to the P1symbol (e.g., a method of having the MSS module (000200) use anotherCSS), and so on.

Meanwhile, the present invention may additionally allocate a preamblesymbol to the preamble region within a signal frame, particularly an NGHframe. Hereinafter, the additional preamble signal will be referred toas an AP1 symbol (Additional Preamble symbol) for simplicity in thedescription of the present invention. In order to enhance the detectionperformance for detecting a mobile broadcast (i.e., NGH) signal, in aconsiderably low SNR condition or a time-selective fading condition, atleast one or more AP1 symbol is added to the signal frame.

At this point, according to the embodiment of the present invention, theAP1 symbol is located between a P1 symbol and a first P2 symbol withinthe preamble region of a signal frame. More specifically, the P1 symboland the AP1 symbol are consecutively transmitted. According to theembodiment of the present invention, if the P2 symbol is not transmittedto the signal frame, the AP1 symbol may be located between the P1 symboland the first data symbol within the preamble region of the signalframe. According to another embodiment of the present invention, the P1symbol and the AP1 symbol may be allocated to non-consecutive positionswithin a single signal frame, so as to be transmitted.

For example, when a signal frame includes an AP1 symbol, the preambleregion of the signal frame is configured of a P1 symbol, at least one ormore AP1 symbols, and at least one or more P2 symbols. And, the dataregion may be configured of a plurality of data symbols (or data OFDMsymbols).

As described in the embodiments for generating the new_system_P1 symbol,according to the embodiment of the present invention, the AP1 symbol maybe generated by modifying the structure of the P1 symbol, shown in (a)of FIG. 4, or by modifying the P1 symbol generator, shown in (b) of FIG.4. According to the embodiment of the present invention, the AP1 symbolmay be generated by modifying both the structure of the P1 symbol, shownin (a) of FIG. 4, and the P1 symbol generator, shown in (b) of FIG. 4.

As described in the embodiment of the present invention, when at least 2or more preamble symbols are used, the present invention is advantageousin that the present invention can be more robust against a burst fadingeffect, which may occur in a mobile fading environment, and that asignal detection performance can be enhanced.

FIG. 5 illustrates an exemplary structure of a P1 symbol and anexemplary structure of an AP1 symbol according to an embodiment of thepresent invention. FIG. 5 shows an example of generating an AP1 symbolby modifying the P1 symbol.

In FIG. 5, P1 symbol, which is shown on the left side, is generated byhaving each of a front portion and an end portion of an effective (orvalid) symbol copied, by having a frequency shift performed as much as+f_(sh), and by having the frequency-shifted copies respectivelypositioned at a front portion (C) and an end portion (B) of theeffective symbol (A). In the present invention, the C portion will bereferred to as a prefix, and the B portion will be referred to as apostfix. More specifically, P1 symbol is configured of a prefix portion,an effective symbol portion, and a postfix portion.

In FIG. 5, AP1 symbol, which is shown on the right side, is generated byhaving each of a front portion and an end portion of an effective (orvalid) symbol copied, by having a frequency shift performed as much as−f_(sh), and by having the frequency-shifted copies respectivelypositioned at a front portion (F) and an end portion (E) of theeffective symbol (D). In the present invention, the F portion will bereferred to as a prefix, and the E portion will be referred to as apostfix. More specifically, AP1 symbol is configured of a prefixportion, an effective symbol portion, and a postfix portion.

Herein, the two frequency-shift values +f_(sh), −f_(sh), which are usedin the P1 symbol and the AP1 symbol, may have the same absolute valueyet be given opposite signs. More specifically, the frequency-shift isperformed in opposite directions. And, the lengths C and F, which arecopied to the front portion of the effective symbol, may be set to havedifferent values. And, the lengths B and E, which are copied to the endportion of the effective symbol, may be set to have different values.Alternatively, the lengths C and F may be set to have different values,and the lengths B and E may be set to have the same value, or viceversa. According to another embodiment of the present invention, aneffective symbol length of the P1 symbol and an effective symbol lengthof the AP1 symbol may be differently determined. And, according to yetanother embodiment of the present invention, a CSS (Complementary SetSequence) may be used for tone selection and data scrambling within theAP1 may be scrambled by AP1.

According to the embodiment of the present invention, the lengths of Cand F, which are copied to the front portion of the effective (or valid)symbol, may be set to have different values, and the lengths of B and E,which are copied to the end portion of the effective (or valid) symbol,may also be set to have different values.

The C,B,F,E lengths according to the present invention may be obtainedby using Equation 1 shown below.Length of C(T _(C))={Length of A(T _(A))/2+30}Length of B(T _(B))={Length of A(T _(A))/2−30}Length of E(T _(F))={Length of D(T _(D))/2+15}Length of E(T _(E))={Length of D(T _(D))/2−15}  Equation 1

As shown in Equation 1, P1 symbol and AP1 symbol have the same frequencyshift value. However, each of the P1 symbol and the AP1 symbol are givenopposite signs. Additionally, in order to determine the lengths of C andB, the present invention determines an offset value being added to orsubtracted from a value corresponding to the length of A (T_(A))/2. And,in order to determine the lengths of F and E, the present inventiondetermines an offset value being added to or subtracted from a valuecorresponding to the length of D (T_(D))/2. Herein, each of the offsetvalues is set up differently. According to the embodiment of the presentinvention, the offset value of P1 symbol is set to 30, and the offsetvalue of AP1 symbol is set to 15. However, the values given in theabove-described examples are merely exemplary. And, therefore, it willbe apparent that the corresponding values may easily be varied orchanged by anyone skilled in the art. Thus, the present invention willnot be limited only to the values presented herein.

According to the present invention, by generating AP1 symbol and an AP1symbol to configure the structure shown in FIG. 5, and by inserting thegenerated symbols to each signal frame, the P1 symbol does not degradethe detection performance of the AP1 symbol, and, conversely, the AP1symbol does not degrade the detection performance of the P1 symbol.Additionally, the detection performance of the P1 symbol is almostidentical to the detection performance of the AP1 symbol. Furthermore,by configuring the symbols so that the P1 symbol and the AP1 symbol havesimilar symbol structures, the complexity level of the receiver may bereduced.

At this point, the P1 symbol and the AP1 symbol may be transmittedconsecutively, or each of the symbols may be allocated to differentpositions within the signal frame and may then be transmitted. And, incase the P1 symbol and AP1 symbol are each allocated to a differentposition within the signal frame, so as to be transmitted, a high timediversity effect may be gained with respect to the preamble symbol.According to the embodiment of the present invention, the P1 symbol andthe AP1 symbol are consecutively transmitted.

FIG. 6 illustrates a block diagram showing a broadcasting signaltransmitting apparatus (or also referred to as a broadcasting signaltransmitter or a transmitter) according to an embodiment of the presentinvention.

As shown in FIG. 6, the broadcasting signal transmitting apparatus mayinclude an input pre-processor (100000), an input processor (100100), aBICM module (100200), a frame builder (100300), and an OFDM generator(100400). Herein, the BICM module (100200) is also referred to as a BICMencoder.

The input stream may include at least one of a TS stream, an Internetprotocol (IP) stream, and a GSE (General Stream Encapsulation) stream(or also referred to as a GS stream).

The input pre-processor (100000) may receive at least one the TS stream,the IP stream, and the GS stream, so as to generate at least one or morePLPs in service units (or service component units) in order to providerobustness.

The input processor (100100) generates a BB frame including at least oneor more of the PLPs generated from the input pre-processor (100000). Incase the input processor (100100) receives a PLP corresponding to aservice, the input processor (100100) may categorize the received PLP asPLPs corresponding to the service components and may, then, generate theBB frame.

The BICM module (100200) adds redundancy to the output of the inputprocessor (100100), so that any error occurring over the transmissionchannel can be corrected, and then the BICM module (100200) performsinterleaving.

The frame builder (100300) maps the plurality of PLPs to thetransmission frame is cell units, so as to complete the transmissionframe (or signal frame) structure.

The OFDM generator (100400) performs OFDM modulation on the input data,so as to generate a baseband signal that can be transmitted to theantenna.

FIG. 9 illustrates a flow chart of a method for receiving a TS in a TSpacket unit, sorting (or categorizing) the received TS with respect toeach component, and transmitting the sorted (or categorized) TS incomponent PLP units.

In order to do so, PSI/SI data such as PAT/PMT may be generated, and aPID is added to each table (S100501). At this point, the PID of a PAT isgiven a fixed value, and the PID of a PMT is signaled to the PAT. ThePID of each component, i.e., video, audio, data ES, and so on, issignaled to the PMT. The process step S100501 may be performed in theinput pre-processor (100000) or may be performed in another block (notshown) and then delivered to the input pre-processor (100000).

The input pre-processor (100000) uses the PID of each component, whichis acquired from the PSI/SI, so as to filter the TS packet and to sort(or categorize) the TS packets in accordance with the media type (i.e.,on a component basis) (S100502). In the TS being sorted by a componentbasis, a position, which was previously occupied by another component,is filled by a null packet. For example, in the video TS, a null packetis inserted in a packet position other than the position of an actualvideo TS packet. The TSs of each component (i.e., the PLP of eachcomponent) having the null packet inserted therein are inputted to theinput processor (100100).

The input processor (100100) deletes the null packet other than thevalid packets within each TS being outputted from the inputpre-processor (100000), and inserts information on the number of deletednull packets (DNPs) with respect to the deleted positions (S100503).Additionally, a synchronization (sync) byte is inserted in front of eachDNP byte, so as to allow the receiving end to perform synchronization.Subsequently, the input processor (100100) slices each TS into apredetermined number of bit units, so as to map the sliced bit units toa BB frame payload, and, then, the input processor (100100) inserts a BBheader to the BB frame payload, so as to generate a BB frame (S100504).

Moreover, the input processor (100100) performs scheduling in order tomap multiple PLPs to the transmission frame, and then the inputprocessor (100100) performs scrambling on the data (i.e., bit stream)within the BB frame (S100505).

The BICM module (100200) adds redundancy to the output of the inputprocessor (100100), so that any error occurring within the transmissionchannel can be corrected, and then, the BICM module (100200) performsinterleaving (S100506).

The frame builder (100300) maps the multiple PLPs being outputted fromthe BICM module (100200) to the transmission frame in cell units inaccordance with the scheduling information, thereby completing thetransmission frame (NGH frame) structure (0100507). The OFDM generator(100400) performs OFDM modulation on the data within the transmissionframe, thereby transmitting the OFDM-modulated data to the antenna(S100508).

FIG. 10 illustrates a flow chart of a method for receiving an IP streamin an IP packet unit, sorting (or categorizing) the received IP streamwith respect to each component, and transmitting the sorted (orcategorized) IP stream in component PLP units.

In order to do so, IP packets including IP service information arecreated (or generated) (S100601). The IP service information may includean NIT, which signals network information, and may include an INT, whichincludes a listed IP address. The IP service information may correspondto a binary type, and FLUTE encoding or RTP encoding may be omitted. TheIP service information is transmitted to a common PLP.

After creating (or generating) bootstrap information for initiation,meta data for service guide, and data for data services (S100602), thecreated information and data are encoded by using a FLUTE session,thereby being outputted in an IP packet format (S100603). Thereafter,the audio/video (A/V) components are sorted (or differentiated) basedupon the RTP media type (S100604), then each of the differentiated (orsorted) components is encoded by using a FLUTE session or an RTPsession, thereby being outputted in an IP packet format (S100605).

The process steps S100601˜S100605 may be performed by the inputpre-processor (100000), or may be performed in another block (not shown)and then delivered to the input pre-processor (100000).

The input processor (100100) may create PLPs by directly using IPpackets that are FLUTE encoded or RTP encoded, or by directly using IPpackets bypassing the FLUTE encoding or RTP encoding processes(S100606). More specifically, by omitting the GSE encapsulating process,the overhead may be reduced.

Subsequently, the input processor (100100) slices each IP stream into apredetermined number of bit units, so as to map the sliced bit units toa BB frame payload, and, then, the input processor (100100) inserts a BBheader to the BB frame payload, so as to generate a BB frame (S100607).

Moreover, the input processor (100100) performs scheduling in order tomap multiple PLPs to the transmission frame, and then the inputprocessor (100100) performs scrambling on the data (i.e., bit stream)within the BB frame (S100505).

The BICM module (100200) adds redundancy to the output of the inputprocessor (100100), so that any error occurring within the transmissionchannel can be corrected, and then, the BICM module (100200) performsinterleaving (S100609).

The frame builder (100300) maps the multiple PLPs being outputted fromthe BICM module (100200) to the transmission frame in cell units inaccordance with the scheduling information, thereby completing thetransmission frame (NGH frame) structure (S100610). The OFDM generator(100400) performs OFDM modulation on the data within the transmissionframe, thereby transmitting the OFDM-modulated data to the antenna(S100611).

Hereinafter, each block included in the broadcast signal transmittingapparatus of FIG. 6 will hereinafter be described in detail.

As described above, according to an embodiment of the present invention,the input pre-processor (100000) may categorize the data correspondingto the service to each component, and, then, the input pre-processor(100000) may perform data processing, so that the data corresponding toeach component can be transmitted to a separate PLP.

The broadcasting signal transmitting apparatus according to the presentinvention may be transmitted to one or more services in PLP units.However, the components being included in one service may be separatedand transmitted in PLP units. In this case, the broadcasting signalreceiving apparatus may identify and process the PLPs including eachcomponent, so as to be capable of providing a single service. In orderto do so, the input pre-processor (100000) according to the presentinvention processes data in component units.

In the following description of the present invention, an example ofgenerating a PLP by receiving a stream having a TS format and an exampleof generating a PLP by receiving a stream having an IP format will beseparately described.

FIG. 9 illustrates a block diagram of the present invention showing astructure of the input pre-processor receiving a stream having a TSformat according to an embodiment of the present invention.

The input pre-processor of FIG. 9 includes a PID filter (101010), aPSI/SI controller (101020), a PSI/SI decoder (101030), a PSI/SImodifying/generating module (101040), a PSI/SI merger (101050), aPAT/PMT merger (101070), component mergers (101090, 101110), and nullpacket inserting modules (101060, 101080, 101100, 101120).

The input pre-processor differentiates the TS packets included in the TSfor each component, and outputs each of the differentiated TS packets toa different PLP. Herein, each TS packet is configured of a header and apayload, and the header includes a Packet Identifier (PID) indicatingthe data to which the header data correspond. The payload may includeany one of a video Elementary Stream (ES), an audio ES, a data ES, and aPSI/SI ES, which are to be transmitted. Additionally, informationincluded in the common PLP may also be referred to as L2 signalinginformation or L2 information/data, and L1 signaling information mayalso be referred to as L1 information.

According to an embodiment of the present invention, when the videocomponent is divided into a base layer video component and anenhancement layer video component, the PID of a TS packet including thebase layer video component and the PID of a TS packet including theenhancement layer video component are different from one another.

More specifically, the PID filter (101010) filters the TS packetsincluded in the TS by using the PID and then outputs the filtered TSpackets through a corresponding PLP path. Since each TS packet isassigned with a PID, which can identify each TS packet, the PID filter(101010) may identify the TS packets corresponding to each component byusing the PID and may then output the identified TS packets through aseparate PLP path. However, since the PID information should be known inorder to perform filtering as described above, the PID filter (101010)first filters the PSI/SI, which is included in the TS packet. The PSI/SIdecoder (101030) decodes the PSI/SI information, which is filtered bythe PID filter (101010), so as to acquire PID information. For example,a PAT having the PID fixed to ‘0’ includes PID information of the PMTand PID information of the NTT, and the PMT includes PID information,such as video, audio, data ES, and so on, corresponding to eachcomponent.

Additionally, the PSI/SI controller (101020) may use the acquired PIDinformation so as to control the PID filter (101010), thereby filteringthe data corresponding to the wanted (or desired) component for each PIDand outputting the filtered data. Since the PSI/SI included in the TSare transmitted by using a predetermined PID, the filtering and dataprocessing procedures may be performed without setting up a separate PIDfilter (101010).

As described above, the PID filter (101010) filters the TS packet foreach component and outputs each of the filtered TS packets through itsrespective PLP path. For example, a TS corresponding to the videocomponent, a TS corresponding to the audio component, and a TScorresponding to the data component are each outputted to the respectivecomponent merger (101090, 101110). And, the component mergers (101090,101110) merge the inputted TS packets so as to configure each componentPLP. For example, the component merger (101090) may receive only the TSpackets corresponding to a base layer video component, or may receiveboth the TS packets corresponding to a base layer video component andthe TS packets corresponding to an enhancement layer video component.Then, the component merger (101090) may merge the received TS packets,so as to configure a single component PLP. Furthermore, TS packetsincluding the PAT/PMT being filtered by and outputted from the PIDfilter (101010) are outputted to the PAT/PMT merger (101070), so as tobe merged.

Thus, when configuring the PLP for each component as described above,even if the receiver scans a channel, the receiver may not be capable ofsearching all of the data corresponding to a single service. Morespecifically, unlike the method of configuring a PLP for each serviceand identifying the configured PLP by using the PSI/SI, since the PLP isconfigured for each component configuring a service in the presentinvention, a component PLP that does not include PSI/SI may exist.Accordingly, in the present invention, in order to locate component PLPsconfiguring a service, PSI/SI, such as a PAT/PMT is added to anarbitrary PLP among the component PLPs configuring the correspondingservice, and a component PLP having service configuration information,such as the above-mentioned PAT/PMT will hereinafter be referred to as abase PLP. When the receiver scans and decodes the base PLP, sinceinformation on the remaining component PLPs for providing a service maybe known, the above-described problem may be resolved.

The PSI/SI modifying/generating module (101040) modifies or generatesPSI/SI that is to be modified or added, such as NIT, SDT, and so on, andthen outputs the modified or generated PSI/SI. For example, in theabove-described component PLP structure, since the base PLP includesinformation on the service configuration, such information on theservice configuration or information on the base PLP is required to besignaled. The input pre-processor may signal the information on the basePLP to at least any one of L1 signaling information and L2 signalinginformation (common PLP). When signaling the information on the base PLPto the L2 signaling information, the PSI/SI modifying/generating module(101040) may signal the information on the base PLP to an NIT/SDT_otheror a PAT/PMT. The information on the base PLP may include informationfor searching the base PLP, information required for extracting the basePLP and decoding the extracted base PLP, information on a PAT/PMTrespective to the service configuration included in the base PLP.Additionally, according to the embodiment of the present invention,information on components for a service having high picture quality/highsound quality, such as SVC, MPEG surround, and so on, is signaled to theL1 signaling information.

The SDT may be indicated as SDT_actual and SDT_other, and the EIT may beindicated as EIT_actual and EIT_other. Herein, the SDT_actual/EIT_actualmay each indicate that the service/event indicated by the respectiveinformation corresponds to service/event included in the current frameor TS, and the SDT_other/EIT_other may each indicate that theservice/event corresponds to service/event included in another frame orTS. In case the PSI/SI extracted from the TS includes a common PLP, thePSI/SI modifying/generating module (101040) may also modify theSDT_actual to an SDT_other or may modify the EIT_actual to an EIT_other.

The PSI/SI merger (101050) merges the signaling information beingoutputted from the PSI/SI modifying/generating module (101040) and thesignaling information being outputted from the PID filter (101010).

The null packet inserting modules (101060, 101080, 101100, 101120)respectively insert a null packet to a place (or positions) whereanother component has been located, so that each component can maintainsynchronization within the TS. Accordingly, a common PLP is outputtedfrom null packet inserting module (101060), and a base PLP is outputtedfrom null packet inserting module (101080). Additionally, thecorresponding component PLPs are outputted from null packet insertingmodules (101100, 101120). Herein, the respective component maycorrespond to a video component, an audio component, a data component,and so on.

As shown in FIG. 9, the input pre-processor, among the inputted TS data,may output data including the PSI/SI through a common PLP path, mayoutput data corresponding to a component PLP, which includes serviceconfiguration information, through a base PLP path, and may output datacorresponding each of the other components through a correspondingcomponent PLP path, and the data corresponding to each of theabove-mentioned PLP path may also be referred to as PLP data or PLP.

The input pre-processor may signal the information on the components,which are configured as described above, to the L1 signalinginformation, so that components can be extracted in PLP units inaccordance with the receiver type. In other words, when a service typeis selected in accordance with the receiver type, the receiver shallprocess the components corresponding to the selected service. In thepresent invention, since the PLP is configured for each component,information on such PLP structure should be included in the L1 signalinginformation, so that the receiver can extract and process the componentscorresponding to the service. Therefore, the input pre-processor mayperform control operations enabling information on the component PLPstructure to be signaled to the L1 signaling information.

(a) and (b) of FIG. 10 illustrate a example of configuring a PLP incomponent units in an input pre-processor according to the presentinvention.

In (a) of FIG. 10, the TS (102010) being configured of TS packetsindicate a TS being inputted to the input-pre-processor of FIG. 9. And,each TS packet includes one of data corresponding to an audio component,data corresponding to a video component, data corresponding to a datacomponent, and data corresponding to a PSI/SI component.

The input pre-processor of FIG. 9 performs the above-describedpre-processing procedure on the TS packets included in the TS stream(102010), so as to differentiate the TS packets for each component,thereby outputting each of the differentiated IS packets to a differentPLP path.

For example, as shown in (b) of FIG. 10, TS packets including NIT, SDT,EIT are outputted through a common ELF path, thereby configuring acommon TS (102020, TS_Common), and TS packets including data of thevideo component are outputted through a video component PLP path,thereby configuring a video component TS (102030, TS_Video).Additionally, the TS packets including data of the audio component areoutputted through an audio component PLP path, thereby configuring anaudio component TS (102040, TS_Audio), and the TS packets including dataof the data component and PAT/PMT information are outputted through adata component PLP path, thereby configuring a data component TS(102050, TS_Other). In another example, TS packets including data of 2or more components may be outputted through a single PLP path, so as toconfigure a single TS. In yet another example, TS packets including dataof a specific component respective to multiple services may be outputtedthrough a single PLP path, so as to configure a single TS.

Also, when the input pre-processor separates TS packets, each beingconfigured a different component, such as audio, video, data, and so on,to each component, in order to maintain synchronization among eachcomponent, the input pre-processor may insert a null packet in theposition of another component in each component TS.

For example, the common TS (102020) inserts a null packet in a positionof a TS packet (or TS packet position) including audio, video, Data,PAT, PMT, and the video component TS (102030) inserts a null packet in aposition of a TS packet (or TS packet position) including audio, NIT,SDT, EIT, Data, PAT, PMT. Moreover, the audio component TS (102040)inserts a null packet in a position of a TS packet (or TS packetposition) including video, NIT, SDT, EIT, Data, PAT, PET, and the datacomponent TS (102050) inserts a null packet in a position of a IS packet(or TS packet position) including audio, video, NIT, SDT, EIT. Theinsertion of the null packet is performed by the null packet insertingmodules (101060, 101080, 101100, 101120) of FIG. 9. Each of the TSs ofeach component, having a null packet included therein, is outputted tothe input processor (100100).

For simplicity in the description of the present invention, the commonTS (102020) having a null packet inserted therein may also be referredto as a common PLP (or PLP data), and the video component TS (102030)having a null packet inserted therein may also be referred to as a videocomponent PLP (or PLP data). Additionally, the audio component TS(102040) having a null packet inserted therein may also be referred toas an audio PLP (or PLP data), and the data component TS (102050) havinga null packet inserted therein may also be referred to as a datacomponent PLP (or PLP data).

(a) and (b) of FIG. 11 illustrate another example of configuring a PLPin component units in an input pre-processor according to the presentinvention.

(a) of FIG. 11 shows an example of TSs being outputted for eachcomponent from the input pre-processor (100000), and (b) of FIG. 11shows an example of TSs being outputted for each component from theinput processor (100100).

The input processor (100100) deletes null packets other than the validpackets from each TS being outputted from the input pre-processor(100000). And, then, the input processor (100100) inserts information ona number of Deleted null packet (DNP) in accordance with the deletedpositions. More specifically, the null packets other than the validpackets are reduced to DNP bytes in each TS.

Referring to each component PLP in (b) of FIG. 11, it will be apparentthat a null packet is deleted from each TS, and that a DNP byteindicating the number of deleted null packets are inserted instead.Additionally, it will also be apparent that a synchronization byte formatching the synchronization in the receiving end is inserted beforeeach DNP byte.

For simplicity in the description of the present invention, as shown in(b) of FIG. 11, a common TS having a null packet deleted therefrom andhaving a DNP byte inserted therein may also be referred to as a commonPLP (or PLP data), and a video component TS having a null packet deletedtherefrom and having a DNP byte inserted therein may also be referred toas a video component PLP (or PLP data). Additionally, an audio componentTS having a null packet deleted therefrom and having a DNP byte insertedtherein may also be referred to as an audio component PLP (or PLP data),and a data component TS having a null packet deleted therefrom andhaving a DNP byte inserted therein may also be referred to as a datacomponent PLP (or PLP data).

FIG. 12 illustrates a flow chart showing a pre-processing method of abroadcasting signal according to an embodiment of the present invention.

FIG. 12 shows an exemplary method of having the input pre-processor(100000) of FIG. 9 separate (or divide) the TS in component units andhaving the input pre-processor (100000) output data of the separatedcomponent unit to each separate PLP path.

The input pre-processor (100000) uses the PID filter (101010), so as tofilter the TS packets including PAT/PMT from an input TS (S105010).Since the PAT/PMT is transmitted as a static PID from the correspondingTS packet, filtering may be performed without any separate PID filtersettings. Also, the PID of the PMT may be acquired from the PAT.

The input pre-processor (100000) uses the PSI/SI decoder (101030), so asto decode the filtered PAT/PMT, thereby acquiring PID information oneach component (S105020). Moreover, the PSI/SI controller (101020) setsup the PID filter (101010) by using the decoded PID information, so asto filter the TS packets for each component, thereby outputting thefiltered TS packets (S105030).

The input pre-processor (100000) may perform other operations inaccordance with the component type (S105040).

When the component type corresponds to the PSI/SI, i.e., when thecomponent type corresponds to common PLP data, the input pre-processor(100000) determines whether or not the PSI/SI requires to be modified(S105050). And, when modification is required, the corresponding PSI/SIis generated or modified (S105050). Additionally, the inputpre-processor (100000) may use the PSI/SI modifying/generating module(101040), so as to signal information on a base PLP to the NIT/SDT_otheror PAT/PMT as described above in the description of FIG. 9, and tomodify NIT, SDT, EIT information. Moreover, the input pre-processor(100000) may use the PSI/SI merger (101050), so as to merge signalinginformation that should be included in the PSI/SI component (S105070).

When the component type does not correspond to the PSI/SI, i.e., whenthe component type corresponds to component PLP data, the inputpre-processor (100000) determines whether or not the data corresponds toa base PLP among the component PLP (S105100). In case of the datarespective to the base PLP, the input pre-processor (100000) merges thePAT/PMT with the data included in the base PLP, and such information onthe base PLP is signaled to the L2 signaling information. In this step,the L2 signaling information may be determined to signal information onthe base PLP to the NIT/SDT_other or PAT/PMT, and the PAT/PMT may bedetermined to signal service configuration information respective to thecomponent structure. And, this may be performed along with theabove-described step (S105060).

The input pre-processor (100000) uses the PAT/PMT merger (101070), so asto merge the PAT/PMT including the service configuration information tothe base PLP data (S105120). Additionally, the input pre-processor(100000) may determine a physical PLP parameter based upon the componenttype, so that the physical PLP parameter can be signaled to the L1signaling information (S105130). In other words, the input pre-processor(100000) may signal information on the component PLP structure to the L1signaling information, so that the receiver can process the componentPLP corresponding to the service.

The input pre-processor (100000) inserts a null packet in PLP data,which are processed in accordance with the component type (S105080). Thenull packet insertion procedure is identical to the procedure describedwith reference to FIG. 9 and FIG. 10. Each set of component PLP datahaving the null packet inserted therein is outputted to a respective PLPpath (S105090).

Hereinafter, the input pre-processor processing data having an IP streamformat will hereinafter be described in detail.

In case of an IP stream, unlike the description presented above, thedata corresponding to the component may be divided in IP packet units.And, the PSI/SI included in the TS may correspond to serviceinformation, and the IP service information may include ESG (ElectronicService Guide; ESG) information, provider information, bootstrapinformation, and so on. The ESG information may include IP addressinformation, port number information, and so on of the service componentand it may be referred to as meta data. According to the embodiment ofthe present invention, the IP stream may be inputted/outputted in GSE(Generic Stream Encapsulation) stream units.

FIG. 13 illustrates a block diagram showing the structure of an inputpre-processor receiving a stream having an IP format according to anembodiment of the present invention.

The input pre-processor (100000) of FIG. 13 includes a UDP/IP filter(106010), an IP service controller (106020), an IP service informationdecoder (106030), an IP service information modifying/generating module(106040), an IP stream merger (106050), GSE encapsulating modules(106060, 106080, 106100, 106120), component mergers (106070, 106090,106110), and a GSE decapsulating module (106130).

The input pre-processor (100000) of FIG. 13 receives a GSE stream or IPstream and differentiates the data included in the received stream foreach component, thereby outputting the differentiated data to adifferent PLP. At this point, a PLP including IP service information maybe referred to as a common PLP, and the common PLP may also be referredto as L2 signaling information or L2 information/data. The L1 signalinginformation may also be referred to as L1 information.

In the present invention, the GSE stream is inputted to the GSEdecapsulation module (106130), and the IP stream is inputted to theUDP/IP filter (106010). The GSE decapsulation module (106130) performsGSE decapsulation on the GSE stream, so as to extract an IP stream,thereby outputting the extracted IP stream to the UDP/IP filter(106010).

The UDP/IP filter (106010) may use a UDP port number and an IP address,and so on, so as to perform filtering on the IP packets, which areincluded in the IP stream, for each component, thereby outputting thefiltered IP packets. Since a UDP port number and an IP address areassigned (or allocated) to each of the IP packets for each component,which are included in the IP stream, the UDP/IP filter (106010) may usethe UDP port number and IP address so as to identify the IP packetcorresponding to each component, thereby outputting each of theidentified IP packets to a separate PLP path. Hereinafter, such UDP portnumber and IP address may also be collectively referred to as an addressor address information.

However, since a UDP port number and an IP address should be known inorder to perform such filtering process, the UDP/IP filter (106010)first filters the IP service information included in the IP stream.Then, the IP service information decoder (106030) decodes the IP serviceinformation, which is filtered by the UDP/IP filter (106010), so as toacquire address information. At this point, the address information maybe acquired from the ESG information among the IP service information.Additionally, the IP service controller (106020) may use the addressinformation, which is acquired from the IP service information decoder(106030), so as to control the UDP/IP filter (106010) and to filter theIP packet corresponding to a desired component for each address, therebyoutputting the filtered IP packet. Since the IP service information,which is included in the IP stream, is transmitted to a predeterminedaddress, an immediate filtering process may be performed without anyseparate settings of the UDP/IP filter (106010).

The UDP/IP filter (106010) first filters the IP packets included in theIP stream for each component and then outputs the filters IP packets toa respective component merger through each PLP path. For example, IPpackets corresponding to the video component are outputted to thecomponent merger (106070), IP packets corresponding to the audiocomponent are outputted to the component merger (106090), and IP packetscorresponding to the data component are outputted to the componentmerger (106110). The component mergers (106070, 106090, 106110) mergethe IP packets of the corresponding component. If the stream beinginputted to the input pre-processor corresponds to a stream having a GSEformat, the output of the component mergers (106070, 106090, 106110) isoutputted as a GSE stream, after being GSE encapsulated by each GSEencapsulating module. And, if the corresponding stream has an IP format,the GSE encapsulating process may be omitted.

When configuring the PLP for each component as described above, thereceiver may not be capable of searching all of the data correspondingto a single service, even when the channel is scanned. Morespecifically, unlike the method of configuring a PLP for each serviceand identifying the configured PLP as IP service information, since thePLP is configured for each component configuring a service, a componentPLP that does not include any IP service information may exist in thepresent invention. Therefore, in the present invention, serviceconfiguration information is added to the IP service information so thatthe component PLPs corresponding to a service can be located and found.

The IP service information modifying/generating module (106040) maymodify or generate IP service information that should be modified oradded, such as ESG information, service provider information, bootstrapinformation, and so on and may, then, output the modified or generatedIP service information. For example, service configuration informationconfiguring a PLP for each component may be signaled to the ESGinformation.

The IP stream merger (106050) merges IP service informationmodified/generated by the IP service information modifying/generatingmodule (106040) and IP service information, such as supplementalinformation, which does not require any modification, thereby outputtingthe merged IP service information to a common PLP path.

According to the embodiment of the present invention, since an IPaddress and a UDP port number are each assigned (or allocated) in IPpacket units to the IP stream, the null packet inserting modules shownin FIG. 9 may be omitted.

As shown in FIG. 13, the input pre-processor may receive an IP stream(or GSE stream) and may output data including IP service information toa common PLP path and may output data corresponding to each component toa component PLP path. Accordingly, as described above, the datacorresponding to each PLP path may also be referred to as PLP data orPLP.

The input pre-processor may signal information on the components, whichare configured as described above, to the L1 signaling information, sothat components can be extracted in PLP units in accordance with thereceiver type. More specifically, when a service type is selected inaccordance with the receiver, the receiver shall process the componentscorresponding to the selected service. In the present invention, since aPLP is configured for each component, the information on such PLPconfiguration is signaled to the L1 signaling information, therebyallowing the receiver to extract the components corresponding to theselected service and to process the extracted components. Accordingly,the input pre-processor may generate information on the PLPconfiguration, so as to perform control operations enabling thegenerated information to be included in the L1 signaling information.

FIG. 14 illustrates an example of configuring a PLP in component unitsin an input pre-processor according to another embodiment of the presentinvention.

In FIG. 14, an IP stream (107010) being configured of IP packetsindicates an IP stream being inputted to the UDP/IP filter (106010) ofthe input pre-processor shown in FIG. 13. And, each IP packet includesone of audio component data, video component data, data component data,and IP service information component data.

The input pre-processor of FIG. 14 performs the above-describedpre-processing procedure on the IP packets included in the IP stream(107010), so as to differentiate the pre-processed IP packets for eachcomponent, thereby outputting each of the differentiated IP packetsthrough a different PLP path.

For example, IP packets including NIT, TNT, bootstrap, ESG informationare outputted through a common PLP path, thereby configuring a common IP(107020, IP_Common), and IP packets including data of the videocomponent are outputted through a video component PLP path, therebyconfiguring a video component IP (107030, IP_Video). Additionally, theIP packets including data of the audio component are outputted throughan audio component PLP path, thereby configuring an audio component IP(107040, IP_Audio), and the IP packets including data of the datacomponent are outputted through a data component PLP path, therebyconfiguring a data component IP (107050, IP_Data). In another example,IP packets including data of 2 or more components may be outputtedthrough a single PLP path, so as to configure a single IP. In yetanother example, IP packets including data of a specific componentrespective to multiple services may be outputted through a single PLPpath, so as to configure a single IP.

At this point, unlike in the TS-based broadcasting, in the IP-basedbroadcasting, a PLP is directly configured without performing nullpacket inserting or deleting processes. This is because a null packet isnot required in the IP stream.

For simplicity in the description of the present invention, a common IPstream (107020) may be referred to as a common PLP (or PLP data), and avideo component IP stream (107030) may be referred to as a videocomponent PLP (or PLP data). Additionally, an audio component IP stream(107040) may be referred to as an audio component PLP (or PLP data), anda data component IP stream (107050) may be referred to as a datacomponent PLP (or PLP data).

Based upon the characteristics of the IP streams, the IP streams of eachPLP path of FIG. 14 are not required to maintain the samesynchronization or order.

FIG. 15 illustrates a flow chart showing a pre-processing method of abroadcasting signal according to another embodiment of the presentinvention.

FIG. 15 shows a processing method of the above-described inputpre-processor (100000) of FIG. 13, so that an IP stream can be dividedin component units, and so that each set of component unit data can beoutputted to a different PLP path.

In case the input stream corresponds to a GSE stream, the inputpre-processor (100000) may use the GSE decapsulating module (106130), soas to decapsulate the GSE stream to an IP stream (S109010). In case theinput stream corresponds to an IP stream, this process step (S109010)may be omitted.

The input pre-processor (100000) may use the UDP/IP filter (106010), soas to filter the ESG information of the input IP stream (S109020). Sincethe ESG information is transmitted from an IP stream to a predeterminedaddress, a filtering procedure may be performed without any separatefilter set-up.

The input pre-processor (100000) may use the IP service informationdecoder (106030), so as to decode the ESG information, which is filteredby the UDP/IP filter (106010) and to acquire address informationrespective to each component included in the IP stream (S109030).Thereafter, the IP service controller (106020) may set up the UDP/IPfilter (106010) by using the address information, which is acquired instep (S109030), so as to filter data for each component and to outputthe filtered data (S109040).

The input pre-processor (100000) performs another operation inaccordance with the component type of the corresponding data (S109050).

In case the component type corresponds to IP service information, i.e.,when the component type corresponds to common PLP data, the inputpre-processor (100000) may determine whether or not the IP serviceinformation requires modification (S109060). Thereafter, whenmodification is required, the corresponding IP service information (ESGinformation, bootstrap information, provider information, and so on) maybe generated or modified (S109070). Then, by using the IP stream merger(106050), IP service information that are to be included in the data,which are transmitted to the common PLP, are merged (S109090).

In case the component type does not correspond to IP serviceinformation, i.e., in case the component type corresponds to componentPLP data, the input pre-processor (100000) sets up a physical parameterbased upon the component type, thereby enabling the physical parameterto be signaled to the L1 signaling information (S109080). In otherwords, the input pre-processor (100000) may signal information on acomponent PLP structure to the L1 signaling information, so that thereceiver can process the component PLP corresponding to the service inaccordance with the component structure of the present invention.

In case the output data format corresponds to a GSE stream, the inputpre-processor (100000) performs GSE encapsulation on the processed PLPdata in accordance with the component type (S109100). In case the outputdata format corresponds to an IP GSE stream, this step may also beomitted. Each set of the component PLP data may be outputted to adifferent PLP path (S109110).

The output of the input pre-processor (100000) is outputted to the inputprocessor (100100).

In the description of the present invention, TS or IP or GSE streams maybe converted to n+1 number of streams that can be independentlyprocessed through the input pre-processor (100000) or the inputprocessor (100100). At this point, the stream that is to beindependently processed may correspond to a complete (or whole) TSstream including a plurality of service components, and may alsocorrespond to a TS stream of a minimum unit including only one servicecomponent (e.g., video or audio, and so on). Similarly, the stream thatis to be independently processed may correspond to a complete (or whole)GSE stream including a plurality of service components or a GSE streamincluding only one service component. Furthermore, the stream that is tobe independently processed may also correspond to a complete (or whole)IP stream including a plurality of service components or an IP streamincluding only one service component.

FIG. 16 illustrates a block diagram showing an exemplary structure of aninput processor (100100) according to an embodiment of the presentinvention.

Herein, FIG. 16 shows an exemplary embodiment of an input processor(100100), wherein the number of input streams is equal to 1. When thenumber of input streams is equal to 1, the input processor (100100) mayinclude an input interface module (110100), a CRC-8 encoder (110200), aBB header inserter (110400), a padding inserter (110400), and a BBscrambler (110500). In the description of FIG. 16, the input interfacemodule (110100), the CRC-8 encoder (110200), and the BB header inserter(110400) will be collectively referred to as a mode adaptation module,and the padding inserter (110400) and the BB scrambler (110500) will becollectively referred to as a stream adaptation module.

The input interface module (110100) maps an input stream in internallogical-bit format for performing FEC (BCH/LDPC) encoding in a BICMmodule (100200). More specifically, the interface module (110100) slicesthe input stream to bit units corresponding to a number of bits requiredfor generating a BB (Base Band or Broadband) frame, so as to map into aBB frame payload. The CRC-8 encoder (110200) performs CRC encoding onthe BB frame payload outputted from the interface module (110100), andthe BB header inserter (110300) inserts a header having a fixed size toa fore-end portion of the BB frame payload, which is processed with CRCencoding, to generate a BB frame.

In case a data size of the inputted bit stream is smaller than a BBframe designated to FEC, the padding inserter (110400) may insert apadding bit to the BB frame, in order to configure the BB frame. The BBscrambler (110500) may perform a bitwise XOR (Exclusive OR) operation ona bit stream of the BB frame by using a PRBS (Pseudo Random BinarySequence), so as to perform randomization. The operations of the BBscrambler (110500) may reduce PAPR (Peak-to-Average Power Ratio) of anOFDM modulation signal transmitted finally.

FIG. 17 illustrates a block diagram showing an exemplary structure of amode adaptation module of an input processor (100100) respective to amulti PLP input according to another embodiment of the presentinvention. More specifically, FIG. 17 shows an embodiment of a modeadaptation module of the input processor (100100) processing a pluralityof PLPs when a type of input stream is a TS format.

The mode adaptation module may include n+1 number of input interfacemodules (111200-0˜n), n+1 number of input stream sync modules(111210-0˜n), n+1 number of delay compensators (111220-0˜n), n+1 numberof null packet deleters (111230-0˜n), n+1 number of CRC (CyclicRedundancy Check) encoders (111240-0˜n), and n+1 number of BB headerinserters (111250-0˜n) operating in parallel to perform mode adaptationon each PLP of the plurality of PLPs.

According to the broadcast signal transmitting apparatus of the presentinvention, by including signaling information that can be commonlyapplied to multiple PLPs, such as a transport layer signal of anMPEG-TS, in a single PLP, and by transmitting the processed PLP, thetransmission efficiency may be increased. As shown in FIG. 17, the PLP0performs such function, and, in the description of the presentinvention, such PLP is referred to as a common PLP. The remaining Pnumber of PLPs excluding the PLP-0, shown in FIG. 17, may be used forperforming data transmission. And, in the description of the presentinvention, such PLP is referred to as a data PLP. Herein, the examplegiven in FIG. 17 is merely exemplary, and, therefore, a plurality ofcommon PLPs, such as PLP0 of FIG. 17, may be used in the presentinvention.

The input interface modules (111200-0˜n) may slice the input stream ofthe corresponding PLP to a number of bits required for generating the BBframe (Base Band frame), so as to map into a BB frame payload.

The input stream sync modules (111210-0˜n) generate sync timinginformation required to recovery TS or GS streams in a receiver andinsert the sync timing information into a BB frame payload. Furthermore,when the receiver performs service recovery, the input stream syncmodules (11210-0˜n) may generate sync timing information based upon alldelays that may occur in the respective channels and transmissionprocessed, so that the corresponding service can be recovered to theinitial timing. Herein, the sync timing information may correspond to anISCR (Input Stream Clock Reference) information. Moreover, the inputstream sync modules (111210-0˜n) synchronize in the receiver by adding async byte.

When multiple PLPs exist, the delay compensators (111220-0˜n) maycompensate the delay difference between each PLP, so that the frame canbe efficiently configured. More specifically, based upon the sync timinginformation inserted by the input stream sync modules (111210-0˜n), thedelay compensators (111220-0˜n) may delay data on PLPs of group units soas to synchronize the PLPs.

In case of a VBR (variable bit rate) service, the null packet deleters(111230-0˜n) may delete the inserted null packets, so as to increase thetransmission efficiency. At this point, a number of deleted null packets(DNPs) may be inserted in the deleted positions, so as to betransmitted.

The CRC encoders (111240-0˜n) performs CRC encoding on the correspondingframe, in order to enhance the transmission reliability of the BB framepayload, thereby adding CRC data.

The BB header inserters (111250-0˜n) inserts a header having a fixedsize on a fore-end portion of the corresponding BB frame payload, sothat the format of the data field can be identified. Herein, the headermay include diverse information, such as Mode Adaptation Typeinformation indicating whether the stream type the of correspondingstream corresponds to a TS, an IP, or a GS, User Packet Lengthinformation, Data Field Length information, User Packet Sync Byteinformation, start address information of a User Packet Sync Byteincluded in the data field, a high efficiency mode indicator, an inputstream sync field, and so on.

FIG. 17 shows an exemplary case when the input stream type correspondsto a TS, and if the input stream type corresponds to an IP stream or aGSE stream, the delay compensators (111220-0˜n) and the null packetremovers (111230-0˜n) may be omitted. For example, since the IP packetis buffered and reproduced in the receiver in accordance with a timestamp, the data are not required to be delayed, and the null packet isnot required to be added/deleted. Furthermore, in accordance with thecharacteristics of the IP streams, the IP streams of each ELF path arenot required to maintain synchronization or the same order. Therefore,input stream sync modules (111210-0˜n) may be omitted. And, since eachof the IP streams has its own CRC, CRC bytes are not required to beadded to the IP streams. Thus, CRC encoders (111240-0˜n) may also beomitted. Accordingly, in the operations of the input processor of FIG.17, the input stream sync modules (111210-0˜n), the delay compensators(111220-0˜n), the null packet removers (111230-0˜n), and CRC encoders(111240-0˜n) may be omitted, or, in case of the IP stream or GSE stream,the blocks may be bypassed.

FIG. 18 illustrates an exemplary structure of a stream adaptation moduleof an input processor (100100) respective to a multi PLP input accordingto another embodiment of the present invention.

The stream adaptation module may include a scheduler (120300), n+1number of frame delayers (130100-0˜n), n+1 number of in-bandsignaling/padding inserters (130200-0˜n), and n+1 number of BBscramblers (130300-0˜n). Furthermore, the stream adaptation module mayinclude L1 signaling generator (130400), two BB scramblers (130500-0,130500-1) for processing L1 signaling information.

The scheduler (120300) may perform scheduling in order to allocatemultiple PLPs to each slot of a transmission frame.

In case the system uses a MIMO method, the scheduler (120300) mayinclude a scheduler for dual polarity MIMO. More specifically, thescheduler (120300) may generate parameters that can be used by a DEMUX,a cell interleaver, a time interleaver of the BICM module (100200).Herein, examples of such parameters may include parameters related to apolarity path, such as an H-path and a V-path. Furthermore, thescheduler (120300) enables a cell mapper to map input cells according toscheduling by outputting L1-dynamic signaling information on a currentframe, apart from in-band signaling.

The frame delayers (130100-0˜n) may delay input data by one transmissionframe, so that scheduling information respective to a next frame can betransmitted through a current frame, in order to perform in-bandsignaling.

The in-band signaling/padding inserters (130200-0˜n) insert thenon-delayed L1-dynamic signaling information to the data being delayedby one transmission frame. In this case, if surplus space exists withinthe input data, a padding bit may be inserted in the surplus space, orin-band signaling information may be inserted in the surplus space.

In order to minimize the correlation between transmission bit sequences,the BB scramblers (130300-0˜n) perform XOR operation on the input bitstream and PRBS, which are outputted from the in-band signaling/paddinginserters (130200-0˜n), so as to randomize the input bit stream. Afterperforming the scrambling procedure, the PAPR of the OFDM modulationsignal, which is finally transmitted, may be reduced.

Additionally, in addition to in-band signaling, the scheduler (120300)may transmit L1-dynamic signaling information of the current frame tothe cell mapper of the frame builder. The cell mapper uses the inputtedinformation, so as to map the input cells to the transmission frame.

In addition to the in-band signaling information, the L1 signalinggenerator (130400) generates L1 signaling information, which istransmitted through a preamble symbol of the transmission frame or adata symbol, which is being spread. Such L1 signaling informationincludes L1-pre-signaling information and L1-post-signaling information.The L1 signaling generator (130400) outputs each of the L1-pre-signalinginformation and the L1-post-signaling information. At this point, theL1-pre-signaling information may be scrambled by the BB scrambler(130500-0), and the L1-post-signaling information may be scrambled bythe BB scrambler (130500-1), both by performing XOR operation with thePRBS. According to another embodiment of the present invention, the L1signaling generator (130400) may output the L1 signaling information,which includes the L1-pre-signaling information and theL1-post-signaling information, and one BB scrambler may also scramblethe outputted L1 signaling information.

A stream adaption module respective to multi PLP input of FIG. 18 isdifferent from a stream adaptation module respective to a single PLPinput of FIG. 16 in that a scheduler (120300), n+1 number of framedelayers (130100-0˜n), n+1 number of in-band scheduling/paddinginserters (130200-0˜n), and so on are added to the stream adaptionmodule respective to multi PLP input of FIG. 18.

Meanwhile, in the present invention, the MISS method may beindependently applied for each set of PLP data, and the MIMO method mayalso be applied.

According to an embodiment of the present invention, the BICM module mayperform MIMO encoding on the MIMO PLP data that are to be transmitted byusing the MIMO method, and the OFDM generator may perform MISO encodingon the MISO PLP data that are to be transmitted by using the MISOmethod. According to another embodiment of the present invention, theBICM module may perform MIMO encoding on the MIMO PLP data that are tobe transmitted by using the MIMO method, and the BICM module may alsoperform MISO encoding on the MISO PLP data that are to be transmitted byusing the MISO method. In this case, the MISO encoding process may beomitted in the OFDM generator.

FIG. 19 illustrates a block diagram showing the structure of a BICMmodule (100200) according to an embodiment of the present invention.Herein, the BICM module performs bit interleaving on the multiple setsinput-processed PLP data, the L1-pre-signaling information, and theL1-post-signaling information and performs encoding for errorcorrection.

For this, according to the embodiment of the present invention, the BICMmodule of FIG. 19 includes a first BICM encoding block (130600)processing MISO PLP data, a second BICM encoding block (130700)processing MIMO PLP data, and a third BICM encoding block (130800)processing signaling information. The third BICM encoding block (130800)then includes a first encoding block for processing L1-pre-signalinginformation and a second encoding block for processing L1-post-signalinginformation.

The signaling information may be processed with MISO or MIMO processingby the OFDM generator. However, since the signaling information includesinformation that are required by the receiver in order to recover thePLP data included in the transmission frame, a greater robustnessbetween the transmission and the reception as compared to that of thePLP data is required. Therefore, according to the embodiment of thepresent invention, the OFDM generator may process the signalinginformation by using the MISO method.

Hereinafter, the data processing method of each block will be described.

The first BICM encoding block (130600) includes an FEC (Forward ErrorCorrection) encoder (131100-0), a bit interleaver (131200-0), a demux(131300-0), a constellation mapper (131400-0), a cell interleaver(131600-0), and a time interleaver (131700-0).

The FEC encoder (131100-0) adds a redundancy to an input bit stream, sothat the receiver can perform correction on an error occurring on thetransmission channel with respect to input processed PLP data and may,then, perform bit stream encoding at a coding rate, such as ¼, ⅓, ⅖. Forexample, the FEC encoder (131100-0) may use a BCH(Bose-Chaudhuri-Hocquengham)/LDPC (Low Density Parity Check) code, so asto add redundancy for error correction and to perform encoding.

The bit interleaver (131200-0) may perform bit interleaving in a singleFEC block unit on the PLP data, which are processed with FEC encoding,so that the error can have robustness against a burst error, which mayoccur during transmission. In this case, the bit interleaver (131200-0)may perform bit interleaving by using two FEC block units. And, asdescribed above, when bit interleaving is performed by using two FECblock units, cells forming a pair in the frame builder, which will bedescribed later on, may each be generated from a different FEC block.Therefore, the broadcasting signal receiver may ensure diversity so asto enhance the receiving performance.

The demux (131300-0) performs demultiplexing in a single FEC block unit.According to an embodiment of the present invention, the demux(131300-0) may adjust the order of the bits configuring a cell, so as tocontrol the robustness of the bit, thereby outputting the cell includingthe bits. More specifically, the demux (131300-0) adjusts the bit outputorder in order to perform dispersed positioning on the distribution ofthe data reliability, which is generated during the LDPC encodingprocess, when the constellation mapper (131400-0) performs symbolmapping in a later process. The demux (131300-0) may performdemultiplexing by using two FEC blocks. As described above, whendemultiplexing is performed by using two FEC blocks, the cellsconfiguring a pair in the frame builder, which will be described indetail later on, may each be generated from a different FEC block.Therefore, the receiver may ensure diversity, so as to gain a moreenhanced receiving performance.

The constellation mapper (131400-0) maps the demultiplexed bit unit PLPdata to the constellation. In this case, the constellation mapper(131400-0) may rotate the constellation by a predetermined angle inaccordance with the modulation type. The rotated constellations may beexpressed as an I-phase (In-phase) element and a Q-phase(Quadrature-phase) element, and the constellation mapper (131400-0) maydelay only the Q-phase element by an arbitrary value. Thereafter, theconstellation mapper (131400-0) may use the In-phase element and thedelayed Q-phase element, so as to remap the demultiplexed PLP data to anew constellation.

The cell interleaver (131600-0) may perform interleaving in cell unitson the PLP data mapped or remapped to the constellation, and the timeinterleaver (131700-0) may perform interleaving on the cell-interleavedPLP data in time units, so as to output the time-interleaved PLP data tothe frame builder. In this case, the time interleaver (131700-0) mayperform interleaving by using 2 FEC blocks. By performing thisprocedure, since the cells configuring a pair in the frame builder,which will be described later on, may each be generated from a differentFEC block, the receiver may ensure diversity so as to enhance thereceiving performance.

The second BICM encoding block (130700) includes an FEC encoder(131100-1), a bit interleaver (131200-1), a demux (131300-1), a firstconstellation mapper (131400-1) and a second constellation mapper(131400-2), an MIMO encoder (131500-1), a first cell interleaver(131600-1), a second cell interleaver (131600-2), a first timeinterleaver (131700-1) and a second time interleaver (131700-2). The FECencoder (131100-1) and the bit interleaver (132100-1) perform the samefunctions as the FEC encoder (131100-0) and the bit interleaver(131200-0) of the first BICM encoding block (130600).

The demux (131300-1) may perform the same functions as the demux(131300-0) of the first BICM encoding block (130600) and mayadditionally perform demultiplexing on the PLP data, so as to output thedemultiplexed PLP data through 2 input paths, which are required for theMIMO transmission. In this case, the transmission characteristics of thedata being transmitted through each input path may be identical to oneanother or may be different from one another.

For example, in case the transmission characteristics of the data beingtransmitted through each of the 2 input paths are different from oneanother, the demux (131300-1) may randomly allocate (or assign) bitwords of the PLP data corresponding to the cell, which is included inone FEC block, to each input path.

In another example, in case the transmission characteristics of the databeing transmitted through each of the 2 input paths are identical to oneanother, the second constellation mapper (131400-2), the second cellinterleaver (131600-2), and the second time interleaver (131700-2),which are marked in dotted lines may not be used.

The first constellation mapper (131400-1) and the second constellationmapper (131400-2) perform the same functions as the constellation mapper(131400-0) of the first BICM encoding block (130600).

The MIMO encoder (131500-1) may apply a MIMO encoding matrix on the PLPdata, which are mapped to the first constellation mapper (131400-1) andthe second constellation mapper (131400-2), so as to perform MIMOencoding on the processed data, thereby outputting the MIMO encoded datato 2 paths. The MIMO encoding method will be described in more detaillater on.

According to an embodiment of the present invention, the first cellinterleaver (131400-1) and the second cell interleaver (131400-2) mayperform cell interleaving only on the PLP data corresponding to half thesize of an FEC block, among the PLP data being MIMO encoded and inputtedthrough each path. Accordingly, the cell interleaving process performedby the first cell interleaver (131400-1) and the second cell interleaver(131400-2) may have the same effect as the interleaving procedureperformed by the cell interleaver (131400-0) of the MISO method includedin the first BICM encoding block (130600). Additionally, the first cellinterleaver (131400-1) and the second cell interleaver (131400-2) areadvantageous in that additional memory are not assigned (or allocated)to the first cell interleaver (131400-1) and the second cell interleaver(131400-2), in order to process the data of multiple paths, and thatcell interleaving may be performed by using the memory settings of thecell interleaver (131400-0).

The first time interleaver (131700-1) and the second time interleaver(131700-1) perform the same functions as the time interleaver (131700-0)of the first BICM encoding block (130600). Also the first timeinterleaver (131700-1) and the second time interleaver (131700-2) mayperform time interleaving on the PLP data being inputted through eachpath by using the same method, or may perform time interleaving by usingdifferent methods.

The third BICM encoding block (130800) includes a first encoding blockprocessing L1-pre-signaling information and a second encoding blockprocessing L1-post-signaling information.

The first encoding block may include an FEC encoder (132100-0), aconstellation mapper (132400-0), a cell interleaver (132500-0), and atime interleaver (132600-0). The second encoding block may include anFEC encoder (132100-1), a bit interleaver (132200), a demux (132300), aconstellation mapper (132400-1), a cell interleaver (132500-1), and atime interleaver (132600-1).

In order to decode the L1 signaling information and data, the receiveris required to accurately and swiftly decode the L1-pre-signalinginformation. Therefore, according to an embodiment of the presentinvention, in order to allow the receiver to accurately and swiftlydecode the L1-pre-signaling information, the present invention will notperform bit interleaving and demultiplexing on the L1-pre-signalinginformation.

For the description on the operations of each block included in thefirst encoding block and the second encoding block, reference may bemade to the description on the operations of the same blocks included inthe first BICM encoding block (130600). And, therefore, detaileddescription of the same will be omitted. However, 2 FEC encoders(132100-0˜1) perform FEC encoding including shortening and puncturing oneach of the inputted L1-pre-signaling information and L1-post-signalinginformation. The FEC encoding process may include BCH encoding and LDPCencoding.

The demuxes (131300-0, 131300-1, 132300) within the first to third BICMencoding blocks of FIG. 19 may also be referred to as bit-cell demuxes.

At this point, the first BICM encoding block (130600) outputs PLP data,which are to be outputted by using the MISO method, through 1 path(STX_k), and the second BICM encoding block (130700) outputs PLP data,which are to be outputted by using the MIMO method, through 2 paths(STX_m, STX_m+1). Additionally, the third BICM encoding block (130800)outputs each of the L1-pre-signaling information and theL2-post-signaling information through one path (STX_pre, STX_post). Forsimplicity of the description of the present invention the pathcorresponding to the STX_k, STX_m, STX_pre, STX_post will be referred toas a first path, and the path corresponding to the STX_m+1 will bereferred to as a second path.

In the structure shown in FIG. 19, the PLP data or signaling data areprocessed in symbol units after being mapped to the constellation.Accordingly, the second BICM encoding block (130700) performs MIMOencoding, cell interleaving, time interleaving on the MIMO PLP data inOFDM units. In this case, the time deinterleaver, the celldeinterleaver, and the MIMO decoder of the broadcasting signal receiverprocess the reception data in symbol units.

According to another embodiment of the BICM module shown in FIG. 19, theMIMO encoder may be provided at the outputting ends of the first timeinterleaver and the second time interleaver.

In this case, the BICM decoder of the broadcast signaling receivershould first perform MIMO decoding on the MIMO PLP data beforeperforming any other operations. And, the MIMO decoded data areoutputted in bit units. Thereafter, the BICM decoder of the broadcastingsignal receiver may perform time deinterleaving and cell deinterleavingon the MIMO decoded data. However, since the data outputted in bit unitsare being inputted, information on the symbol units of the inputted datais required. More specifically, since the broadcasting signal receivershould to store information on symbol mapping of the input bits, whichare required in the deinterleaving process, the complexity in the memoryof the receiver may be increased.

Conversely, if the MIMO encoder is located between the constellationmapper and the cell interleaver, as shown in FIG. 19, the respectiveBICM decoder of the broadcasting signal receiver may perform MIMOdecoding on the symbol unit data, after performing both timedeinterleaving and cell deinterleaving in symbol units. In this case,since the bit unit data being processed with MIM decoding are processedwith the constellation demapping procedure, additional (or separate)information on symbol mapping is not required. Accordingly, if the MIMOencoder is located after the constellation mapper, the complexity in thememory of the receiver may be reduced, as compared to when the MIMOencoder is located after the time interleaver.

FIG. 20 illustrates a block diagram showing the structure of a framebuilder according to an embodiment of the present invention. Herein, theframe builder is adequate for processing the output of the BICM moduleshown in FIG. 19. In the present invention, the frame builder will alsobe referred to as a frame mapper.

The frame builder of FIG. 20 includes a first frame building block(133100) receiving MISO PLP data, MIMO PLP data, L1-pre-signaling data,and L1-post-signaling data of the first path, and a second framebuilding block (133500) receiving MIMO PLP data of the second path. Thedata of the first path are processed with a modulation procedure in theOFDM generator, so as to be transmitted through the first antenna(Tx_1), and after being processed with the modulation procedure in theOFDM generator, the data of the second path are transmitted through thesecond antenna (Tx_2).

According to an embodiment of the present invention, the first framebuilding block (133100) includes a delay compensator (133200), a firstcell mapper (133300), and a first frequency interleaver (133400), andthe second frame building block (133500) includes a second cell mapper(133600) for processing data being inputted through the second path anda second frequency interleaver (133700).

The first cell mapper (133300) and the first frequency interleaver(133400) and the second cell mapper (133600) and the second frequencyinterleaver (133700) may operate identically with respect to the firstpath and the second path or may operate independently from one anotherwith respect to the first path and the second path.

Hereinafter, the data processing method of the blocks included in thefirst frame building block (133100) and the second frame building block(133500) will be described.

In order to perform cell mapping, the delay compensator (133200)compensates for the delay generated in the signaling information andmatches the time synchronization with the inputted PLPs. Morespecifically, a delay corresponding to one transmission frame in theL1-pre-signaling data or the L1-post-signaling data and a delayoccurring due to the encoding process of the third BICM encoding block(130800) are both compensated. Since the L1 signaling information mayinclude not only the information on the current information frame butalso the information on the next transmission frame, during the inputprocessing procedure, the L1 signaling information is delayed by oneframe than the PLP data that are currently being inputted. By performingsuch procedure, one transmission frame may transmit L1 signalinginformation including both information on the current transmission frameand information on the next transmission frame.

The first cell mapper (133300) and the second cell mapper (133600) mapthe symbol unit PLP data and the L1 signaling data being inputtedthrough each path to subcarriers of the OFDM symbol, which is includedin the transmission frame, in cell units in accordance with thescheduling information included in the signaling information.

Additionally, the first cell mapper (133300) and the second cell mapper(133600) respectively map the MISO PLP data and the MIMO PLP data tosubcarriers of one OFDM symbol in cell units.

The PLP data, which are being inputted to the first cell mapper (133300)and the second cell mapper (133600) through the first path and thesecond path may include common PLP data, MISO, MIMO PLP data, and eachsub-slice processor may perform sub-slicing on the PLP data cells, inorder to gain a diversity effect, so as to map the processed PLP datacell within the transmission frame.

Additionally, although the MISO PLP data and the L1-pre-signaling andpost-signaling data are inputted only through the first path, since theMIMO PLP data are inputted through both the first path and the secondpath, the operation of the cell mapper may vary depending upon whichdata are being inputted.

Hereinafter, the detailed operations will be described.

First of all, the first cell mapper (133300) and the second cell mapper(133600) may each receive the same MISO PLP data that are inputtedthrough the first path, and the first cell mapper (133300) and thesecond cell mapper (133600) may also receive the same L1-pre and postsignaling information, which are outputted from the delay compensator(133200). In this case, the first cell mapper (133300) and the secondcell mapper (133600) may map each set of input data, so that thecorresponding data can be allocated to the subcarrier of the OFDM symbolwith the transmission frame.

Secondly, among the first cell mapper (133300) and the second cellmapper (133600), only the first cell mapper (133300) may receive theMISO PLP data and the delay-compensated L1-pre and post signaling data.In this case, the second cell mapper (133600) may perform mapping onlyon the MIMO PLP.

The first frequency interleaver (133400) and the second frequencyinterleaver (133700) may perform frequency interleaving on the databeing inputted through each path in cell units, and may output thefrequency interleaved data to the OFDM generator through each path.

In this case, the first frequency interleaver (133400) and the secondfrequency interleaver (133700) perform interleaving on the cellspositioned in the transmission frame within the frequency domain basedupon the OFDM symbol. Additionally, when the second cell mapper (133600)receives only the MIMO PLP data, the second frequency interleaver(133700) may also perform interleaving only on the MIMO PLP data.

FIG. 21 illustrates a block diagram showing the structure of an OFDMgenerator according to an embodiment of the present invention, which isadequate for processing the output of the frame builder shown in FIG.20. Most particularly, FIG. 21 shows an example of transmitting abroadcasting signal through 2 transmission antennae by using the MISO orMIMO method. According to the embodiment of the present invention, apolarity multiplexing MIMO method is used in the present invention.

The OFDM generator of FIG. 21 is configured of an MISO encoder (134100),2 pilot inserters (134100-0, 134100-1), 2 IFFT modules (134200-0,134200-1), 2 PAPR reduction modules (134300-0, 134300-1), 2

GI inserting modules (134400-0, 134400-1), 2 P1 symbol inserting modules(134500-0, 134500-1), 2 AP1 symbol inserting modules (134600-0,134600-1), and 2 DACs (134700-0, 134700-1). In the present invention, ablock modulating a broadcasting signal that is to be transmitted througha first transmission antenna (Tx1) will be referred to as a firsttransmitting unit, and a block modulating a broadcasting signal that isto be transmitted through a second transmission antenna (Tx2) will bereferred to as a second transmitting unit. The first transmitting unitincludes a pilot inserter (134100-0), an IFFT module (134200-0), a PAPRreduction module (134300-0), a GI inserting module (134400-0), a P1symbol inserting module (134500-0), an AP1 symbol inserting module(134600-0), and a DAC (134700-0). The second transmitting unit includesa pilot inserter (134100-1), an IFFT module (134200-1), a PAPR reductionmodule (134300-1), a GI inserting module (134400-1), a P1 symbolinserting module (134500-1), an AP1 symbol inserting module (134600-1),and a DAC (134700-1).

In order to perform transmission through 2 transmission antennae, theMISO encoder (134100) performs MISO encoding, so that transmissiondiversity can be gained for signals being inputted through the first andsecond paths. Then, the MISO encoder may output the processed signals toeach pilot inserter (134100-0, 134100-1). If data MIMO-encoded by theBICM module are inputted, the MISO encoder (134100) may bypass the inputdata to the pilot inserters (134100-0, 134100-1).

More specifically, if the data being inputted through the first path andthe second path correspond to MISO PLP data or L1-pre and post signalingdata, the MISO encoder (134100) may use an MISO encoding matrix so as toperform MISO encoding in OFDM symbol units, thereby outputting theprocessed data to the pilot inserters (134100-0, 134100-1). In thiscase, the data may also be inputted to the MISO encoder (134100) onlythrough any one of the first path and the second path. According to theembodiment of the present invention, examples of the MISO encodingmatrix may include OSTBC (Orthogonal Space-Time Block Code)/OSFBC(Orthogonal Space Frequency Block Code or Alamouti code).

The pilot inserters (134100-0, 134100-1) may insert a pilot signalhaving a specific pilot pattern in a respective position within thesignal frame, so that the receiver can perform transmission channelestimation and time/frequency synchronization, thereby outputting theprocessed data to the IFFT modules (134200-0, 134200-1). At this point,the pilot pattern information may be signaled to the AP1 signalinginformation and may also be signaled to the L1 signaling information.Alternatively, the pilot pattern information may be signaled to both theAP1 signaling information and the L1 signaling information.

By performing inverse fast Fourier transform, the IFFT modules(134200-0, 134200-1) convert each signal having a pilot inserted thereinto time domain signals, thereby outputting the processed signals to thePAPR reduction modules (134300-0, 134300-1).

The PAPR reduction module (134300-0, 134300-1) may reduce the PAIR ofthe time domain signals, thereby outputting the processed signals to theGI inserting modules (134400-0, 134400-1). The PAPR reduction modules(134300-0, 134300-1) may use at least one of an ACE (ActiveConstellation Extension) method or a Tone Reservation method, so as toreduce the PAPR from the modulated OFDM symbol. Additionally, necessary(or required) information may be fed-back to the pilot inserters(134100-0, 134100-1) in accordance with a PAIR reduction algorithm.

By copying the last portion of an effective OFDM symbol to a frontportion of the corresponding OFDM symbol, the GI inserting modules(134400-0, 134400-1) may insert a guard interval in a cyclic prefixformat, thereby outputting the processed symbol (or data) to the P1symbol inserting modules (134500-0, 134500-1). The GI information issignaled to the L1 pre signaling information. And, a portion of the GIinformation is signaled to the P1 signaling information.

The P1 symbol inserting modules (134500-0, 134500-1) may insert a P1symbol in a starting portion of each signal frame, thereby outputtingthe processed data (or signal) to the AP1 symbol inserting modules(134600-0, 134600-1).

The AP1 symbol inserting modules (134600-0, 134600-1) insert an AP1symbol after each P1 symbol, thereby outputting the processed data tothe DACs (134700-0, 134700-1). Herein, the insertion of the P1 symbolsand the AP1 symbols may be performed by the P1 symbol inserting modules(134500-0, 134500-1), and, in this case, the AP1 symbol insertingmodules (134600-0, 134600-1) may be omitted.

The DACs (134700-0, 134700-1) may first convert the each signal framehaving the AP1 symbol inserted therein to analog signals, therebytransmitting the converted signal through the corresponding transmissionantenna (Tx1, Tx2).

FIG. 22 illustrates a block diagram showing a structure of a BICM moduleaccording to another embodiment of the present invention, wherein theBICM module performs bit interleaving and encoding for error correctionon a plurality of input-processed PLP data, L1-pre-signalinginformation, and L1-post-signaling information.

In order to do so, according to the embodiment of the present invention,the BICM module of FIG. 22 includes a first BICM encoding block (135001)processing MISO PLP data, a second BICM encoding block (135002)processing MIMO PLP data, and a third BICM encoding block (135003)processing signaling information. The third BICM encoding block (135003)then includes a first encoding block for processing L1-pre-signalinginformation, and a second encoding block for processingL1-post-signaling information. At this point, since the signalinginformation requires greater robustness between the transmission andreception, as compared to the PLP data, according to the embodiment ofthe present invention, the signaling information is processed by usingthe MISO method.

For example, a MISO encoder (135500-0) is equipped between aconstellation mapper (135400-0) and first and second cell interleavers(135600-0, 135600-1) of the first BICM encoding block (135001) shown inFIG. 22, and a MIMO encoder (135500-3) is equipped between first andsecond constellation mappers (135400-3, 135400-4) and first and secondcell interleavers (135600-3, 135600-4) of the second BICM encoding block(135002). And, a MISO encoder (136500-0) is equipped between a firstconstellation mapper (136400-0) and first and second cell interleavers(136600-0, 136600-1) of the third BICM encoding block (135003), and aMISO encoder (136500-3) is equipped between a second constellationmapper (136400-3) and third and fourth cell interleavers (136600-3,136600-4) of the third BICM encoding block (135003).

In FIG. 22, an FEC encoder (135100-0), a bit interleaver (135200-0), aDEMUX (135300-0), and a constellation mapper (135400-0) of the firstBICM encoding block (153001) respectively perform the same operations asthe FEC encoder (131100-0), the bit interleaver (131200-0), the DEMUX(131300-0), and the constellation mapper (131400-0) of the first BICMencoding block (130600) shown in FIG. 19. And, therefore, for detaileddescription of the corresponding blocks, reference may be made on thepreviously described blocks.

In FIG. 22, since the operations of each block included in the secondBICM encoding block (153200) are identical to the operations of eachblock included in the second BICM encoding block (130700) of FIG. 19,for detailed description of the corresponding blocks, reference may bemade on the previously described blocks.

In FIG. 22, FEC encoders (136100-0, 136100-3), constellation mappers(136400-0, 132600-3), a bit interleaver (136200), and a DEMUX (136300)of the third BICM encoding block (153001) respectively perform the sameoperations as the FEC encoders (132100-0, 132100-1), the constellationmappers (132400-0, 132400-1), the bit interleaver (132200), and theDEMUX (132300) shown in FIG. 19. And, therefore, for detaileddescription of the corresponding blocks, reference may be made on thepreviously described blocks.

The DEMUXes (135300-0, 135300-3, 136300) included in the first to thirdBICM modules of FIG. 22 may also be referred to as bit-cell DEMUXes.

Herein, only the parts associated with the MISO encoder will bedescribed in detail.

More specifically, the MISO encoder (135500-0) of the first BICMencoding block (1351) performs MISO encoding on the PLP data, which aremapped to the constellation, by using an MISO encoding matrix, therebygenerating 2 output signals. Among the 2 output signals, one outputsignal is inputted to the first cell interleaver (135600-0) through afirst path, and the other output signal is inputted to the second cellinterleaver (135600-1) through a second path. Thus, transmissiondiversity may be gained. In the present invention, as an exemplaryembodiment of the MISO encoding method, an OSTBC (Orthogonal Space-TimeBlock Code)/OSFBC (Orthogonal Space Frequency Block Code/Alamouti code)method may be used. Data that are interleaved in cell units by the firstcell interleaver (135600-0) are inputted to a first time interleaver(135700-0), so as to be interleaved in time units. Additionally, datathat are interleaved in cell units by the second cell interleaver(135600-1) are inputted to a second time interleaver (135700-1), so asto be interleaved in time units.

For the description of the MISO encoders (136500-0, 136500-1), the firstto fourth cell interleavers (136600-0˜136600-3), and the first to fourthtime interleavers (136700-0˜136700-3) of the third BICM encoding block(135003), reference may be made to the description of the operations ofthe same blocks, which are included in the first BICM encoding block(135001). Therefore, detailed description of the same will be omittedfor simplicity.

At this point, the first BICM encoding block (135001) outputs MISO PLPdata through 2 different paths (STX_k, STX_k+1), and the second BICMencoding block (135002) outputs MIMO PLP data through 2 different paths(STX_m, STX_m+1). Additionally, the third BICM encoding block (135003)outputs signaling data through 2 different paths (STX_pre, STX_pre+1 andSTX_post, STX_post+1) with respect to the L1-pre-signaling informationand the L1-post-signaling information. Hereinafter, the pathcorresponding to STX_k, STX_m, STX_pre, and STX_post will be referred toas a first path, and the path corresponding to STX_k+1, STX_m+1,STX_pre+1, and STX_post+1 will be referred to as a second path, forsimplicity.

As another example of the BICM module shown in FIG. 22, a MISO encoderand a MIMO encoder may be equipped at each output end of the timeinterleaver. In this case, the respective BICM decoder of thebroadcasting signal receiver first performs MISO decoding or MIMOdecoding on each set of data and, then, outputs the data processed withMISO decoding or MIMO decoding in bit units. At this point, the databeing outputted from the MISO decoder or the MIMO decoder correspond tobit-unit likelihood (or probability) information. Accordingly,hereinafter, the BICM decoder of the broadcasting signal receiver mayperform time deinterleaving and cell deinterleaving procedures on theMISO or MIMO decoded data. However, since data that are outputted in bitunits are being inputted, information of symbol-unit data is alsorequired. Therefore, since the broadcasting signal receiver is requiredto store information on symbol mapping of the input bits, which isrequired for the deinterleaving procedures, the complexity level in thememory of the broadcasting signal receiver may be increased.

Conversely, as shown in FIG. 22, if the MISO encoder and the MIMOencoder are both located between the constellation mapper and the cellinterleaver, the respective BICM decoder of the broadcasting signalreceiver may perform MISO/MIMO decoder after performing both timedeinterleaving and cell de-interleaving in symbol units. In this case,the bit-unit data (or data bits) that are processed with MISO/MIMOdecoding are processed with a constellation demapping procedure. And,therefore, separate information on symbol mapping is not required.Accordingly, when the MISO/MIMO encoder is located at the end of theconstellation mapper, the complexity level of the memory included in thereceiver may be decreased as compared to when the MISO/MIMO encoder islocated at the end of the time interleaver.

FIG. 23 illustrates a block diagram showing a structure of a framebuilder according to another embodiment of the present invention, whichis adequate for processing the output of the BICM module shown in FIG.22.

The frame builder of FIG. 23 consists of a first frame building block(136801) receiving the MISO PLP data, MIMO PLP data, theL1-pre-signaling information, and the L1-post-signaling information ofthe first path (STX_k, STX_m, STX_pre, STX_post), and a second framebuilding block (136901) receiving the MISO PLP data, MIMO PLP data, theL1-pre-signaling information, and the L1-post-signaling information ofthe second path (STX_k+1, STX_m+1, STX_pre+1, STX_post+1). The data ofthe first path are transmitted through a first antenna (Tx_1) afterbeing processed with a modulation process in the OFDM generator, and thedata of the second path are transmitted through a second antenna (Tx_2)after being processed with a modulation process in the OFDM generator.

The first frame building block (136801) may include a first delaycompensator (136800-1), a first pair-wise cell mapper (136800-2), and afirst pair-wise frequency interleaver (136800-3), and the second framebuilding block (136901) may include a second delay compensator(136900-1), a second pair-wise cell mapper (136900-2), and a secondpair-wise frequency interleaver (136900-3) for processing the data beinginputted through the second path.

The first pair-wise cell mapper (136800-2) and the first pair-wisefrequency interleaver (136800-3) and the second pair-wise cell mapper(136900-2) and the second pair-wise frequency interleaver (136900-3) maybe identically operated with respect to each of the first path and thesecond path and may also be independently operated.

Hereinafter, the data processing method of the blocks included in eachof the first frame building block (136801) and the second frame buildingblock (136901) will be described in detail.

The first delay compensator (136800-1) and the second delay compensator(136900-1) compensates for both the delay by one transmission frameapplied to the L1-pre-signaling data or L1-post-signaling data and thedelay caused by the encoding process of the BICM module. The L1signaling information may include the information on the currenttransmission frame as well as the information on the next transmissionframe. Therefore, during the above-described input processing procedure,the L1 signaling information is delayed by one frame as compared to thePLP data, which are currently being inputted. By performing thisprocedure, one transmission frame may be capable of transmitting the L1signaling information including information on the current transmissionframe and information on the next transmission frame.

The first pair-wise cell mapper (136800-2) and the second pair-wise cellmapper (136900-2) map respectively map the symbol unit PLP data and theL1 signaling data, which are inputted through each path, in cell unitsto the subcarrier of the OFDM symbol within the transmission frame.

In this case, the PLP data being inputted through each path may includecommon PLP data and MISO-MIMO-encoded PLP data. And, a sub-sliceprocessor may perform sub-slicing on the PLP data cells and map thesub-sliced PLP data cells to the transmission frame, so as to gaindiversity.

Additionally, the first pair-wise cell mapper (136800-2) and the secondpair-wise cell mapper (136900-2) may pair 2 consecutive input cells andmay map the paired cells to the transmission frame.

In order to increase the MISO signal recovery performance of thereceiver, when performing MISO encoding, the MISO transmission channelis required to ensure coherence between the channels. Accordingly, inorder to ensure coherence between the channels, the first pair-wise cellmapper (136800-2) and the second pair-wise cell mapper (136900-2) mayrespectively pair cells, which are generated from the same PLP data, andmay map the paired cells to the subcarrier of the OFDM modulation,thereby maximizing the coherence between the channels. In other words,according to the embodiment of the present invention, since the MISOencoder is located in the BICM encoder of the frame builder, the framestructure may be configured by the frame builder in pair units basedupon such MISO encoding.

Moreover, as described above, when bit interleaving or time interleavingis performed by the bit interleaver and the time interleaver of the BICMmodule by using two FEC blocks, since the two input cells that aregrouped to form a pair may be generated from different FEC blocks, thereceiver may be capable of ensuring diversity and may gain highreception performance.

The first pair-wise frequency interleaver (136800-3) and the secondpair-wise frequency interleaver (136900-3) may perform frequencyinterleaving in cell units on the data being inputted through each path.Then, the first pair-wise frequency interleaver (136800-3) and thesecond pair-wise frequency interleaver (136900-3) may output thefrequency interleaved data to the OFDM generator through each path.

In this case, the first pair-wise frequency interleaver (136800-3) andthe second pair-wise frequency interleaver (136900-3) may group 2consecutive input cells in pairs and may process each cell pair as asingle interleaving unit, thereby performing frequency interleaving.This is for maximizing the coherence between the channels.

FIG. 24 illustrates a block diagram showing the structure of an OFDMgenerator according to another embodiment of the present invention,which is adequate for processing the output of the frame builder shownin FIG. 23. Most particularly, FIG. 24 shows an example of abroadcasting signal being transmitted through 2 transmission antennae byusing the MISO or MIMO method. According to the embodiment of thepresent invention, the present invention uses a polarity multiplexingMIMO method.

The OFDM generator of FIG. 24 does not include an MISO encoder, and theOFDM generator of FIG. 21 includes an MISO encoder. With the exceptionof such differences, the two OFDM generators are identical to oneanother. Therefore, for the detailed description of the operationsperformed by each block shown in FIG. 24, reference may be made to thedescription on the operations of the same blocks shown in FIG. 21. Morespecifically, the OFDM generator of FIG. 24 receives data, which areMISO encoded or MIMO encoded by the BICM module, from the frame builder.

Meanwhile, according to the embodiment of the present invention, theMIMO encoder (131500-1) within the BICM module of FIG. 19 or the MIMOencoder (135500-1) within the BICM module of FIG. 22 may perform MIMOencoding by using an MIMO encoding matrix. Hereinafter, the MIMO encoderindicates the MIMO encoder (131500-1) within the BICM module of FIG. 19.The MIMO encoding matrix according to the present invention may includespatial multiplexing, a GC (Golden code), a Full-rate full diversitycode, a Linear dispersion code, and so on. Alternatively, the presentinvention may use encoding matrices according to a first embodiment to athird embodiment of the present invention, which are described below, soas to perform MIMO encoding.

FIG. 25 illustrates a method for transmitting and receiving data inaccordance with an MIMO transmission of an SM method in a channelenvironment according to an exemplary embodiment of the presentinvention.

The MIMO transmitting system may send out input signal 1 (S1) and inputsignal 2 (S2) to each of the transmission antenna 1 and transmissionantenna 2 by using the SM method.

The reception antenna 1 may receive a signal through two differentpaths, and, in the channel environment of FIG. 25, a received signal ofreception antenna 1 may correspond to S1*h11+S2*h21, and a receivedsignal of reception antenna 2 may correspond to S1*h12+S2*h22. Thereceiving end may acquire S1 and S2 by performing channel estimation,thereby being capable of recovering data.

As a scenario corresponding to when a transmission path and a receptionpath are independent from one another, such environment will hereinafterbe referred to as an un-correlated channel environment. Conversely, acorrelation between channels of a transmission path and a receptionpath, such as in a LOS (Line Of Sight) environment, may be highlycorrelated, and such channel environment may be referred to as a fullycorrelated channel environment.

A case when the channels in the MIMO correspond to fully correlatedchannel corresponds to a case when each parameter of a 2 by 2 matrixindicating a channel, in FIG. 25, is equal to 1 (h11=h12=h21=h22=1). Atthis point, the reception antenna 1 and the reception antenna 2 receivethe same receiving signals signal (S1+S2). In other words, the receptionantenna 1 and the reception antenna 2 receive a signal that isequivalent to a signal adding all of the transmitting signals.Eventually, when each of the signals being transmitted from 2 differenttransmission antennae passes through the same channel, and when thesignals are received by 2 reception antennae, the receiving signalsreceived by the receiver, i.e., the two sets of data added by thechannel, are incapable of expressing both symbols S1 and S2. Referringto FIG. 25, in case of the fully correlated channel environment, thereceiver is incapable of receiving a 16-QAM symbol, which corresponds toa combination of signal S1, which is expressed as a 4-QAM symbol, andsignal 2, which is also expressed as a 4-QAM symbol. And, as shown inthe right side of the drawing, since the received receives signalsS1+S2, which is expressed as 9 symbols, S1 and S2 cannot be separated(or divided), so as to be recovered.

The receiving signal, which has passed through the fully correlatedchannel, may be expressed as a signal combining (or adding) transmittingsignals being transmitted from the transmitting system. Morespecifically, when 2 antennae are used, and when the transmitting systemtransmits a first transmitting signal and a second transmitting signal,the MIMO encoding method will hereinafter be described in detail underthe assumption that the receiving signal passing through the fullycorrelated channel corresponds to a signal consisting of a combinationof the first transmitting signal and the second transmitting signal.

In this case, even if the receiver is in a very high SNR environment,the receiver is incapable of recovering the signal transmitted via MIMOby using the SM method. In case of a communication system, since it isassumed that the system generally performs two-way (or bi-directional)communication, the system may perform processes of changing thetransmission method by notifying such channel situation to thetransmitter through a feedback channel between the transmitter and thereceiver. However, in case of a broadcasting system, it may be difficultto perform two-way (or bi-directional) communication through a feedbackchannel. Also, since the number of receivers being covered by eachtransmitter is large, and since the coverage range become wider, it maybe difficult for the broadcasting system to respond to the diversechanges in the channel environment. Accordingly, when the SM method isused in such fully correlated channel environment, the receiver cannotuse the respective service. And, unless the coverage of the broadcastingnetwork is reduced, it may be difficult for the system to respond tosuch environment, thereby causing an increase in cost.

Hereinafter, a method for overcoming a case when the correlation betweenMIMO channels is equal to 1, i.e., a case when the channel environmentcorresponds to a fully correlated channel environment, will be describedin detail.

In order to overcome these problems and to ensure low system complexity,high data transmission efficiency, and high signal recovery performancein various channel environments, multiple input signals may be processedwith MIMO processing, in accordance with a MIMO matrix and a parametervalue of the MIMO matrix, thereby being capable of outputting multipletransmission signals. According to the embodiment of the presentinvention, the broadcasting signal transmitting apparatus may use theMIMO encoder, so as to perform MIMO encoding on a broadcasting signaland to transmit the processed signal through a plurality of transmissionantennae, and the broadcasting signal receiving apparatus may use theMIMO decoder, so as to perform MIMO decoding on the broadcasting signal,which is received through a plurality of reception antennae. In thepresent invention, the MIMO encoder may also be referred to as an MIMOprocessor, and the MIMO decoder may also be referred to as an ML(Maximum Likelihood) detector (or ML decoder).

At this point, the modulation method may be expressed as M-QAM(Quadrature Amplitude Modulation) or N-QAM. More specifically, when M(or N) is equal to 2, the modulation method may be expressed as 2-QAM,which indicates a BPSK (Binary Phase Shift Keying) method, and when M(or N) is equal to 4, the modulation method may be expressed as 4-QAM,which indicates QPSK (Quadrature Phase Shift Keying). Moreover, when M(or N) is equal to 16, the modulation method may be expressed as 16-QAM,when M (or N) is equal to 64, the modulation method may be expressed as64-QAM, and when M (or N) is equal to 256, the modulation method may beexpressed as 256-QAM. Herein, M, N each indicates a number of symbolsbeing used for modulation.

For example, M+M QAM MIMO indicates that QAM symbols, which are used forMIMO encoding and MIMO decoding, use the same M-QAM. In another example,M+N QAM MIMO indicates that QAM symbols, which are used for MIMOencoding and MIMO decoding, use different M-QAM and N-QAM.

In the present invention, in order to overcome the case when thecorrelation between the MIMO channels is equal to 1, i.e., when the MINDchannel corresponds to a fully correlated channel, the MIMO systemaccording to the present invention may be designed so that a signal,which is received after passing through a channel, can satisfy thefollowing conditions (or requirements).

1) A received signal should be capable of expressing both originalsignals.

2) A minimum Euclidean distance of the received signal should beincreased, so that a symbol error rate can be reduced. Herein, aEuclidean distance refers to a distance between coordinates over aconstellation.

3) A hamming distance characteristic of the received signal should beadvantageous, so that the bit error rate can be reduced. Herein, when abit value corresponding to binary codes each having the same number ofbits do not match, the Hamming distance indicates a number of binarycodes having non-matching bit values.

In order to meet with the above-described requirements, the presentinvention proposes a MIMO encoding method using an MIMO encoding matrix,which includes an encoding parameter (also referred to as an encodingcoefficient) a, as shown below in Equation 2.

$\begin{matrix}\begin{bmatrix}1 & a \\a & {- 1}\end{bmatrix} & {{Equation}\mspace{14mu} 2}\end{matrix}$

When an MIMO encoder performs encoding on input signals S1 and S2 byusing an MIMO encoding matrix, as shown in Equation 2, the receptionsignal 1 (Rx1) and the reception signal 2 (Rx2), which are received byreception antenna 1 and reception antenna 2, may be calculated by usingEquation 3 shown below. And, most particularly, in case the MIMO channelcorresponds to a fully correlated channel, the signals are calculated byusing the last line shown in Equation 3.Rx ₁ =h ₁₁(S1+aS2)+h ₂₁(aS1−S2)Rx ₂ =h ₁₂(S1+aS2)+h ₂₂(aS1−S2), if h ₁₁ =h ₂₁ =h ₁₂ =h ₂₂ =h,R=Rx ₁ =Rx ₂ =h{(a+1)S1+(a−1)S2}  Equation 3

First of all, in case the MIMO channel corresponds to an un-correlatedchannel, the reception signal 1 (Rx1) may be calculated asRx1=h₁₁(S1+a*S2)+h₂₁(a*S1−S2), and the reception signal 2 (Rx2) may becalculated as Rx2=h₁₂(S1+a*S2)+h₂₂(a*S1−S2), so that S1 and S2 can havethe same power. Accordingly, all of the gain of the MIMO system may beused as in the SM method.

Meanwhile, when the MIMO channel corresponds to a fully correlatedchannel, the reception signals (R=Rx1=Rx2) may be acquired asR=h{(a+1)S1+(a−1)S2}. Thus, S1 and S2 may be separately acquired.Herein, S1 and S2 may also be designed to have different power levels,and by using such different power levels robustness may be ensured.

In other words, the MIMO encoder may encoder input signals, so thatinput signals S1 and S2 can have different power levels, in accordancewith an encoding parameter (also referred to as an encoding coefficient)a, and so that S1 and S2 can also be received in different distributionformats in a fully correlated channel. For example, by performing anencoding process on S1 and S2, so that S1 and S2 can have differentpower levels, and by transmitting the encoded S1 and S2 to aconstellation having different Euclidean distances due to anormalization process, even when signals go through a fully correlatedchannel, the receiver may separate (or divide) the input signals andrecover the separated signals accordingly.

Based upon a normalization factor, the MIMO encoding matrix of Equation3 may be expressed as shown below in Equation 4.

$\begin{matrix}{{\frac{1}{\sqrt{1 + a^{2}}}\left\lbrack \begin{matrix}1 & a \\a & {- 1}\end{matrix} \right\rbrack} = {\quad{\left\lbrack {\begin{matrix}\frac{1}{\sqrt{1 + a^{2}}} \\\frac{a}{\sqrt{1 + a^{2}}}\end{matrix}\begin{matrix}\frac{a}{\sqrt{1 + a^{2}}} \\\frac{- 1}{\sqrt{1 + a^{2}}}\end{matrix}} \right\rbrack = \left\lbrack \begin{matrix}{\cos\;\theta} & {\sin\;\theta} \\{\sin\;\theta} & {{- \cos}\;\theta}\end{matrix} \right\rbrack}}} & {{Equation}\mspace{14mu} 4}\end{matrix}$

A MIMO encoding method of the MIMO encoder, which uses the MIMO encodingmatrix shown in Equation 4, may be considered as a method of rotatinginput signals by an arbitrary angle (Theta), which can be expresses asan encoding parameter a, so as to divide the signal into a cosineelement of the rotated signal and a sine element (or real number elementand imaginary (or false) number element) and to assign +/− signs to eachof the divided elements, thereby transmitting the processed signal toanother antenna. For example, the MIMO encoder may perform encoding sothat a cosine element of input signal S1 and a sine element of inputsignal S2 can be transmitted to one transmission antenna, and that asine element of input signal S1 and a cosine element, having a − signadded thereto, of input signal S2 can be transmitted to anothertransmission antenna. A rotation angle may vary depending upon a changein an encoding parameter value a, and power distribution between inputsignals S1 and S2 may vary depending upon a value and angle of thecorresponding parameter. Since the varied power distribution may beexpressed as a distance (i.e., Euclidean distance) between symbolcoordinates in a constellation. Even if the input signals pass through afully correlated channel from the receiving end, such encoded inputsignals may be expressed in the form of a different constellation, sothat the input signals can be identified, divided, and recovered.

In other words, since a Euclidean distance between transmission signalsvaries to a level corresponding to the distribution of the varied power,the transmission signals received by the receiving end may be expressedin the form of distinguishable constellations each having a differentEuclidean distance. More specifically, the MIMO encoder may encode inputsignal S1 and input signal S2 as a signal having another Euclideandistance in accordance with the value a. And, such encoded transmissionsignals may be received by the receiving end in distinguishable (oridentifiable) constellations and may be recovered accordingly.

The MIMO encoding of the input signal, which is performed by using theabove-described MIMO encoding matrix, may be expressed as shown below inEquation 5.

$\begin{matrix}{\begin{bmatrix}{X\; 1} \\{X\; 2}\end{bmatrix} = {{\frac{1}{\sqrt{1 + a^{2}}}\begin{bmatrix}1 & a \\a & {- 1}\end{bmatrix}}\begin{bmatrix}{S\; 1} \\{S\; 2}\end{bmatrix}}} & {{Equation}\mspace{14mu} 5}\end{matrix}$

In Equation 5, S1 and S2 represent normalized QAM symbols of aconstellation, to which input signal S1 and input signal S2 are mappedby a constellation mapper of a MIMO path. And, each of X1 and X2respectively represents a MIMO-encoded symbol. In other words, the MIMOencoder may apply the matrix, which is shown in Equation 5, to a 1^(st)input signal including symbols corresponding to S1 and to a 2^(nd) inputsignal including symbols corresponding to S2, so as to transmit a 1^(st)transmission signal including symbols corresponding to X1 and symbols ofa transmission signal X2 including symbols corresponding to X2.

The MIMO encoder may perform MIMO encoding on input signals by suing theabove-described MIMO encoding matrix, and may also perform encoding byadditionally adjusting an encoding parameter value a. More specifically,the consideration and adjustment of an additional data recoveryperformance of the MIMO transmitting and receiving system may beoptimized by adjusting the encoding parameter value a. And, this willhereinafter be described in more detail.

1. First Embodiment: MIMO Encoding Method of Optimizing an EncodingParameter Value a Based Upon a Euclidean Distance (Fully Correlated MIMOChannel)

The value a, which corresponds to an encoding parameter, may becalculated by using the above-described MIMO encoding matrix whileconsidering the Euclidean distance. According to the first embodiment ofthe present invention, a signal that is combined in the receiving end,after passing through a fully correlated MIMO channel, may be given aEuclidean distance, such as a QAM signal.

The first embodiment of the present invention proposes a method ofoptimizing the value a, so that each symbol included in a symbolconstellation of reception signals, which have passed through the fullycorrelated channel, can have the same Euclidean distance. Morespecifically, when the MIMO encoder uses the above-described MIMO matrixso as to encode the input signals, the MIMO encoder may calculate ordetermine the value of the encoding parameter a, so that the Euclideandistance between the reception symbols can be consistent (or equal) inthe constellation of the reception signals (i.e., a combined signal ofthe 1^(st) transmission signal St1 and the 2^(nd) transmission signalSt2), which have passed through the fully correlated channel. And,accordingly, the MIMO encoder may perform an encoding process. Suchvalue a may be expressed as Equation 6 shown below, in accordance with acombination of the modulation methods.

$\begin{matrix}{a = \left\{ \begin{matrix}3 & {,{{{for}\mspace{14mu}{QPSK}} + {QPSK}}} \\{\left( {4 + \sqrt{5}} \right)\text{/}\left( {4 - \sqrt{5}} \right)} & {,{{{for}\mspace{14mu}{QPSK}} + {16\;{QAM}}}} \\0.6 & {,{{{for}\mspace{14mu} 16\;{QAM}} + {16\;{QAM}}}}\end{matrix} \right.} & {{Equation}\mspace{14mu} 6}\end{matrix}$

In other words, since the distribution and constellation of atransmission and reception symbol vary depending upon the modulationmethod of reception signals and the combination of the receptionsignals, the value a may also be varied in order to optimize theEuclidean distance.

In other words, in case of the first embodiment of the presentinvention, for example, in a signal wherein a 1^(st) input signal of4-QAM and a 2^(nd) input signal of 4-QAM are MIMO-encoded and combinedwith outputted 1^(st) transmission signal and 2^(nd) transmissionsignals, the value a may be determined so that the constellation of thecombined signal is identical to the constellation of a 16-QAM signal.The MIMO encoding method according to the first embodiment of thepresent invention shows a more excellent SNR performance as compared towhen using the GC method or the SM method in the fully correlated MIMOchannel. Most particularly, the SNR gain according to the firstembodiment of the present invention becomes higher as the coding rate ofthe outer code increases, conversely, in case of the SM method, in acoding rate of ⅖ or higher, decoding cannot be performed at all in thefully correlated channel, and, regardless of the SNR, even the servicereception cannot be performed. Additionally, the MIMO encoding methodaccording to the first embodiment of the present invention shows thesame performance in an un-correlated channel as the SM method, and theperformance is more excellent as compared to the other methods.Therefore, the MIMO encoding method according to the first embodiment ofthe present invention may provide a better performance by using a systemhaving a lower complexity level as compared to the GC method. And, theMIMO encoding method according to the first embodiment of the presentinvention may provide a more excellent performance in the fullycorrelated channel, as compared to when using the SM method having asimilar complexity level.

According to another embodiment of the present invention, whenperforming MIMO encoding, a GC subset may be used as the MIMO encodingmatrix. And, in this case, the MIMO encoding matrix may be expressed asshown below in Equation 7.

$\begin{matrix}{{\begin{bmatrix}\alpha & {\alpha\;\theta} \\{i\overset{\_}{\alpha}} & {i\overset{\_}{\alpha}\overset{\_}{\theta}}\end{bmatrix}\begin{bmatrix}{S\; 1} \\{S\; 2}\end{bmatrix}},{\alpha = {1 + {\left( {1 - \theta} \right)i}}},{\overset{\_}{\alpha} = {1 + {\left( {1 - \overset{\_}{\theta}} \right)i}}},{\theta = \frac{1 + \sqrt{5}}{2}},{\overset{\_}{\theta} = \frac{1 - \sqrt{5}}{2}}} & {{Equation}\mspace{14mu} 7}\end{matrix}$

In case of using an encoding matrix Equation 7, the performance is shownto be better than the first embodiment of the present invention.

When the MIMO encoding process using the GC subset performed in thefully correlated MIMO channel is compared with the MIMO encoding processperformed according to the first embodiment of the present invention (SMOPT1) in the fully correlated MIMO channel, in case of using the firstembodiment of the present invention (SM OPT1), a minimum Euclideandistance within the constellation of the reception signal may be greaterthan the case of using the GC subset. However, the SNR performancerespective to the case of using the GC subset (SM OLDP Golden) is shownto be better than the case of using the first embodiment of the presentinvention.

2. Second Embodiment: MIMO Encoding Method Considering Gray Mapping inAddition to a Euclidean Distance

The second embodiment of the present invention proposes a MIMO encodingmethod enabling a reception signal, which has passed through the fullycorrelated channel in a state when the value a is determined to have avalue that can optimize the Euclidean distance, as in the firstembodiment of the present invention, to have gray mapping appliedthereto.

In the MIMO encoding method according to the second embodiment of thepresent invention, among the input signals S1 and S2, signs of the realnumber part and the imaginary number part of input signal S2 may bechanged in accordance with the S1 value, so that gray mapping can beperformed in the receiving end. The change in the data value included inS2 may be performed by using the method shown below in Equation 8.

More specifically, the MIMO encoder may use the MIMO encoding matrixused in the first embodiment of the present invention and may performMIMO encoding by changing the sign of the input signal S2 in accordancewith the value of S1. In other words, as shown in Equation 8, afterdeciding the sign of input signal S2 in accordance with the sign ofinput signal S1, MIMO encoding matrix may be applied to the decidedinput signal S1 and input signal S2, as described above, so that 1^(st)transmission signal St1 and 2^(nd) transmission signal St2 can beoutputted.S1=b ₀ b ₁ . . . b _(N−1) , N=log₂ M, M=QAM size of S1real(S1)=b ₀ b ₂ . . . b _(N−2)imag(S1)=b ₁ b ₃ . . . b _(N−1)for i=1 . . . N−1si=sq=1if i=index of real(S1) and b ₁=1si=−siif i=index of imag(S1) and b ₁=1sq=−sqend forS2=si·real(S2)+i·sq·imag(S2)  Equation 8

As shown in Equation 8, an XOR operation is performed on each of the bitvalues allocated to the real number part and the imaginary number partof S1 among the input signal S1 and the input signal S2. Then, basedupon the result of the XOR operation, the signs respective to the realnumber part and the imaginary number part of S2 may be decided.Additionally, when transmission signal 1 and transmission 2, whichrespectively correspond to input signal S1 and input signal S2 havingthe MIMO encoding matrix applied thereto, as described above, aretransmitted from transmission antenna 1 and transmission antenna 2, thereception symbols of the reception signal, having passed through thefully correlated channel and being received by the receiver, may havegray mapping. Therefore, the hamming distance between neighboringsymbols within the constellation may not exceed the value of 2.

Since the (M*N)-QAM signal (or (M*M)-QAM signal) received by thereceiving end has a minimum (or uniform) Euclidean distance and graymapping, in case of the second embodiment of the present invention, thesame performance of the SIMO method may also be expected in the fullycorrelated MIMO channel. However, when the ML decoder decodes thereception signal and acquired S1 and S2, since the S2 value depends uponS1, the complexity level may be increased. And, in an un-correlated MIMOchannel, the performance is likely to be degraded due to a correlationbetween the input signals.

3. Third Embodiment: MIMO Encoding Method Determining an MIMO EncodingParameter while Considering a Hamming Distance in Addition to aEuclidean Distance

The third embodiment of the present invention proposes a method ofperforming MIMO encoding by determining a value a, so that the overallconstellation of the reception signal does not have a minimum Euclideandistance, as in the first embodiment of the present invention, and sothat the Euclidean distance can be optimized based upon a hammingdistance of the reception signal.

That is, in the third embodiment, the Euclidean distance is beingadjusted in order to compensate a difference in the recovery performancerespective to a difference in the hamming distance with a difference inthe power level. More specifically, with respect to neighboring symbols,wherein a difference in the number of bits of one symbol is 2 times thatof another symbol, a performance degradation respective to a differencein the hamming distance, which may occur during the reception signalrecovery, may be compensated by adjusting (i.e., increasing) theEuclidean distance, so that the section having 2 times the hammingdistance can be provided with greater power level. First of all, arelative Euclidean distance is determined with respect to a receptionsignal, which corresponds to a combination of the 2 transmission signals(St1, St2) both being received by the receiving end. Referring to theabove-described Equation 3, it will be apparent that the minimumEuclidean distance of a 16-QAM symbol having a decreasing power level isequal to 2(a−1), and that the minimum Euclidean distance of a 16-QAMsymbol having an increasing power level is equal to 2(a+1) (this isbecause one reception signal is expressed as R=h{(a+1)S1+(a−1)S2}).

In the third embodiment, the MIMO encoder uses the above-described MIMOmatrix in order to perform MIMO encoding, so that each input signal canbe assigned with a different power level, and so that each input signalcan have a different Euclidean distance. That is, according to the thirdembodiment of the present invention, the MIMO encoder may calculate anddetermine the value of an encoding parameter a, so that input signalsbeing assigned with different power levels can each have a Euclideandistance, which can compensate for the difference in the hammingdistance. Thus, the MIMO encoding process may be performed. Moreover,such value of a may be represented as Equation 9 shown below, accordingto a combination of the modulation methods.

$\begin{matrix}{a = \left\{ \begin{matrix}{\sqrt{2} + 1} & {,{{{for}\mspace{14mu}{QPSK}} + {QPSK}}} \\{\left( {\sqrt{2} + 3 + \sqrt{5}} \right)\text{/}\left( {\sqrt{2} + 3 - \sqrt{5}} \right)} & {,{{{for}\mspace{14mu}{QPSK}} + {16\;{QAM}}}} \\{\left( {\sqrt{2} + 4} \right)\text{/}\left( {\sqrt{2} + 2} \right)} & {,{{{for}\mspace{14mu} 16\;{QAM}} + {16\;{QAM}}}}\end{matrix} \right.} & {{Equation}\mspace{14mu} 9}\end{matrix}$

In case of QPSK+16QAM MIMO, it will be assumed that the value proposedabove corresponds to when the constellation mapper has performednormalization of the power level to 1, after performing QAM modulationon input signal S1 and input signal S2 by respectively using QPSK and16QAM. In case the normalization process is not performed, the value amay be corrected accordingly.

Additionally, in addition to the value proposed in the case ofQPSK+16QAM MIMO, a value of 4.0 may be used as the value a. In case ofQPSK+16QAM MIMO, this is due to the characteristic enabling the combinedsignal to express both S1 and S2, even in a case of using the SM methodin the fully correlated channel. In this case, in order to compensatefor the performance in a high coding rate of an outer code, a valueproximate to 4.0 may be used instead of the value calculated by usingEquation 9.

Based upon the description presented above, when comparing the secondembodiment of the present invention with the third embodiment of thepresent invention, in the fully correlated MIMO channel, the secondembodiment of the present invention shows a performance identical tothat of the SIMO, thereby causing no loss in the performance.Accordingly, the disadvantages of the MIMO method of the fullycorrelated MIMO channel may be enhanced. However, according to thesecond embodiment of the present invention, due to the MIMO encodingprocess, since the input data S1 and S2 are not independent from oneanother, the input data S2 may vary in accordance with the input dataS1, thereby causing degradation in the performance in an un-relatedchannel. Therefore, the reception of S1 and any decoding error occurringduring the reception of S1 may be reflected to S2, thereby causingadditional decoding error in S2. In order to resolve such problem, thepresent invention may use an iterative ML detection process.

The iterative ML detection includes an outer code in an iterative loop.Then, the iterative ML detection process uses a soft posterioriprobability value of S1, which is outputted from the outer code, as apriori probability value of the ML detector. Accordingly, by reducingany detection error, any possible application of the detection error ofS1 to the S2 detection may be reduced. By using this method, when usingthe MIMO encoding method according to the second embodiment of thepresent invention, the fully correlated MIMO channel may show theperformance of an SIMO system, and the un-correlated MIMO channel mayshow the performance of the SM method.

The MIMO encoding process according to the third embodiment of thepresent invention is devised and designed so that the reception signalbeing received through the fully correlated MIMO channel can considerboth the hamming distance and the Euclidean distance. Accordingly, thethird embodiment of the present invention shows an excellent performancein the fully correlated MIMO channel. And, in comparison with the SMmethod, since the MIMO encoding process according to the thirdembodiment of the present invention shows no loss in performance in theun-correlated MIMO channel, it is verified that the gain in both theMIMO transmission and the MIMO reception can be used. In this case,since the complexity level of the receiver is similar to the complexitylevel corresponding to the SM method, the MIMO encoding processaccording to the third embodiment of the present invention is alsoadvantageous in implementing the receiver of the present invention.

Meanwhile, when performing MIMO transmission/reception, a powerimbalance situation may occur between the signals that are beingtransmitted through each communication path. More specifically, signalsthat are transmitted from multiple transmission antennae may bedelivered to the receiver at different power levels. And, in a worstcase, only one signal being transmitted from a transmission antenna maybe received. Hereinafter, an MIMO encoding method that can minimizeperformance degradation in such power imbalance situation will bedescribed in detail. Most particularly, an MIMO encoding method using anMIMO encoding matrix including an encoding coefficient, as describedabove, and additionally considering such power imbalance situation willbe described in detail.

4. Fourth Embodiment: MIMO Encoding Method Optimizing Value a Based Upona Euclidean Distance of a Transmission Signal

By using the above-described MIMO encoding matrix, the value a may becalculated based upon the Euclidean distance of a transmission signal.In a MIMO system having two transmission antennae and two receptionantennae, when input signal S1 corresponds to an M-QAM symbol, and wheninput signal S2 corresponds to an N-QAM symbol, signal S1+S2, whichpasses through a fully correlated MIMO channel, corresponds to an(M*N)-QAM signal.

As described above in Embodiment 1, based upon the reception signal, thevalue a may be decided by optimizing the Euclidean distance. However, inthis case the decoding performance may be degraded in a power imbalancesituation. Therefore, when the Euclidean distance is optimized basedupon the transmission signals of the transmitting end, the degradationin the performance that may occur during a power imbalance situation atthe receiving end may be minimized. The value a for optimizing theEuclidean distance based upon the transmission signals may be calculatedby using Equation 10 shown below.

$\begin{matrix}{a = \left\{ \begin{matrix}2 & {,{{{for}\mspace{14mu}{QPSK}} + {QPSK}}} \\4 & {,{{{for}\mspace{14mu} 16\;{QAM}} + {16\;{QAM}}}}\end{matrix} \right.} & {{Equation}\mspace{14mu} 10}\end{matrix}$

When using the MIMO encoding method shown in Embodiment 4, since theEuclidean distance of the transmission signal, which is received duringa power imbalance situation, is optimized, it will be apparent that thedegradation in the receiving performance has been minimized.

However, in case the symbol types of the inputted symbol are differentfrom one another, as in the QPSK+16-QAM transmission method, anothervalue is required to be used. This is because, when the modulationschemes (or methods) of the inputted signals, which are used during theMIMO transmission, are different from one another, and when theoptimized value a is used on only one transmission antenna, a trade-offeffect may occur, wherein the performance of another transmissionantenna (or other transmission antennae) is relatively degraded.

5. Embodiment 5: MIMO Encoding Method Based Upon Gray Mapping inAddition to a Euclidean Distance of a Transmission Signal

In Embodiment 5, as described in Embodiment 4, the present inventionproposes an MIMO encoding method enabling a transmission signal, whichhas passed through a fully correlated channel, to have gray mapping in apower imbalance situation, wherein value a is determined so that theEuclidean distance of the transmission signal can be optimized.

In the MIMO encoding method according to the fifth embodiment of thepresent invention, among the input signals S1 and S2, the signs of thereal number part and the imaginary number part of S2 may be changed inaccordance with the value of S1, so that each of the transmissionsignals can be processed with gray mapping. The change in the value ofthe data included in S2 may be performed by using the method such asEquation 2, which is described above in Embodiment 2.

More specifically, as shown in Equation 8, XOR operations may beperformed on each of the bit values assigned to the real number part andthe imaginary number part of input signals S1 and S2. And, the signs ofthe real number part and the imaginary number part of S2 may be decidedbased upon the result of the XOR operations, so that transmission signal1 and transmission signal 2, each having gray mapping, can betransmitted from antenna 1 and antenna 2.

Since the (M*N)-QAM or (M*M-QAM) signal being transmitted from thetransmitting end has a minimum Euclidean distance and gray mapping, incase of the fifth embodiment, even in the power imbalance situation, aperformance identical to that of the SIMO method may be anticipated.However, when the ML decoder decodes the reception signal, so as toacquire S1 and S2, since the value of S2 is dependent upon S1, thecomplexity level may be increased.

6. Embodiment 6: MIMO Encoding Method Based Upon a Hamming Distance inAddition to a Euclidean Distance of a Transmission Signal

In Embodiment 6, instead of enabling the entire constellation of thetransmission signal to have a minimum Euclidean distance, as describedin Embodiment 4, the present invention determines the value a so thatthe Euclidean distance can be optimized based upon the Hamming distanceof the transmission signal. More specifically, as described above in thethird embodiment of the present invention, an encoding matrix may bedesigned, so that the squared value of the Euclidean distance betweenneighboring (or adjacent) constellation points, when the Hammingdistance between the constellation points is equal to 2, can be equal to2 times the squared value of the Euclidean distance between neighboring(or adjacent) constellation points, when the Hamming distance betweenthe constellation points is equal to 1. In other words, the Euclideandistance may be adjusted so that a difference in the recoveryperformance, which is caused by a difference in the Hamming distance,can be compensated by a difference in power levels.

A method for determining the value a according to an embodiment of thepresent invention will hereinafter be described in detail.

For example, in the transmission signal, the Hamming distancecorresponding to the section between the symbols within theconstellation, which indicates the first input signal, is equal to ½ ofthe Hamming distance corresponding to the section in-between the symbolswithin the constellation, which indicates the first input signal.Therefore, the Euclidean distance may be adjusted so that the differencein the Hamming distance can be compensated by having the inner sectionmaintain a power level that is two times higher than the power level ofa neighboring (or adjacent) section. In other words, the neighboringsection has a Hamming distance that is two times greater than that ofthe inner section. More specifically, referring to the symbols beingadjacent to (or neighboring) one another, since the difference in thenumber of bits of one symbol is two time greater (or smaller) than itsadjacent (or neighboring) symbol, the Euclidean distance may beextended, so that the section having a Hamming distance 2 times largerthan that of another section can be supplied with a greater power level.Thus, the degradation in the performance, which is caused by thedifference in the Hamming distance, can be compensated when recoveringthe reception signal. In other words, the Euclidean distance isadjusted, so that the difference in the recovery performance, which iscaused by the difference in the Hamming distance, can be compensated bya difference in the power level.

First of all, a relative Euclidean distance in the constellationrespective to each transmission signal (St1, St2), each beingtransmitted from the transmitting end, is determined. Referring to theabove-described Equation 3, it will be apparent that the minimumEuclidean distance of a 16-QAM symbol having a decreasing power level isequal to (a−1), and that the minimum Euclidean distance of a 16-QAMsymbol having an increasing power level is equal to (a+1). (This isbecause one transmission signal is expressed as R h{(a+1)S1+(a−1)S2}.)Then, by using the above-described conditions, the value a may beobtained, and the respective calculation may be expressed by usingEquation 11 shown below.

$\begin{matrix}{a = \left\{ \begin{matrix}{\sqrt{2} + 1} & {,{{{for}\mspace{14mu}{QPSK}} + {QPSK}}} \\{\sqrt{2} + 3} & {,{{{for}\mspace{14mu} 16\;{QAM}} + {16\;{QAM}}}}\end{matrix} \right.} & {{Equation}\mspace{14mu} 11}\end{matrix}$

However, as described in the QPSK+16-QAM transmission method, when thesymbol types of each input signals are difference from one another, adifferent value should be used. This is because, when the modulationschemes (or methods) of the inputted signals, which are used during theMIMO transmission, are different from one another, and when theoptimized value ‘a’ is used on only one transmission antenna, atrade-off effect may occur, wherein the performance of anothertransmission antenna (or other transmission antennae) is relativelydegraded.

FIG. 26 illustrates a block diagram showing an exemplary structure of abroadcast signal receiving apparatus according to an embodiment of thepresent invention.

The broadcast signal receiving apparatus according to the presentinvention may include an OFDM demodulator (138100), a frame demapper(138200), a BICM decoder (138300), and an output processor (138400).

The frame demapper (138200) may also be referred to as a frame parser.

The OFDM demodulator (138100) converts time domain signals to frequencydomain signals. Herein, the time domain signals correspond to signalsbeing received through multiple reception antennae and then beingconverted to digital signals. Among the signals being converted tofrequency domain signals, the frame demapper (138200) outputs the PLPsdesignated to required services. The BICM decider (138300) correctserrors that occur due to the transmission channel, and the outputprocessor (138300) performs procedures required for generating an outputTS or IP or GS stream.

FIG. 27 illustrates a block diagram showing an exemplary structure of anOFDM demodulator (131800) of the broadcast signal receiving apparatus.More specifically, the OFDM demodulator of FIG. 27 performs an inverseprocess of the OFDM generator of FIG. 21. According to the embodiment ofthe present invention, in order to receive a broadcast signal, which istransmitted by using a MIMO or MISO, two reception antennae (Rx1, Rx2)are used. An embodiment according to the present invention accordinguses a polarity multiplexing MIMO method.

The OFDM demodulator (138100) of FIG. 27 includes a first receiving unitconfigured to perform OFDM demodulation on a signal, which is receivedthrough the first reception antenna (Rx1), and a second receiving unitconfigured to perform OFDM demodulation on a signal, which is receivedthrough the second reception antenna (Rx2). The first receiving unit mayinclude a tuner (139000-0), an ADC (139100-0), a P1 symbol detector(139200-0), an AP1 symbol detector (139250-0), a time/frequencysynchronization unit (139300-0), a GI remover (139400-0), an FFT module(139500-0), and a channel estimator (139600-0). And, the secondreceiving unit may include a tuner (139000-1), an ADC (139100-1), a P1symbol detector (139200-1), an AP1 symbol detector (139250-1), atime/frequency synchronization unit (139300-1), a GI remover (139400-1),an FFT module (139500-1), and a channel estimator (139600-1). The OFDMdemodulator further includes an MISO decoder (139700) at a outputterminal of the first and second receiving unit. The MISO (139700) willbe referred to as an MISO processor. The description of the presentinvention will be mostly made based upon the blocks included in thefirst receiving unit. And, since the operations of the blocks includedin the second receiving unit are identical to those of the blocksincluded in the first receiving unit, the detailed description of thesame will be omitted for simplicity.

The tuner (139000-0) of the first receiving unit may select only asignal of a desired (or wanted) frequency band. Also, according to theembodiment of the present invention, in order to be applied to the TFSsystem, the tuner (139000-0) may have an FH (Frequency Hopping)function. The ADC (139100-0) converts the analog broadcasting signal,which is inputted through a first path (e.g., V-path), to a digitalbroadcasting signal.

The P1 symbol detector (139200-0) detects a P1 symbol from the digitalbroadcast signal, and the P1 symbol detector (139200-0) then uses P1signaling information, which is carried by the P1 symbol, so as todetermine the frame structure of the currently received signal. The AP1symbol detector (139250-0) may detect and decode an AP1 symbol, whichtransmits the AP1 signaling information included in the digitalbroadcasting signal, so as to gain pilot pattern information of thecurrent signal frame. Herein, the detection and decoding of the P1symbol and the AP1 symbol may be performed by the P1 symbol detector(139200-0), and, in this case, the AP1 symbol detector (139250-0) may beomitted.

The time/frequency synchronization unit (139300-0) uses at least one ofthe P1 signaling information and the AP1 signaling information so as toperform GI extraction and time synchronization and carrier frequencysynchronization.

The GI remover (139400-0) removes the GI from the synchronized signal,and the FFT module (139500-0) converts the GI-removed signal to afrequency domain signal.

The channel estimator (139600-0) uses a pilot signal being inserted inthe frequency domain signal, so as to estimate a transmission channelstarting from a transmission antenna to a reception antenna. The channelestimator (139600-0) performs channel equalization compensating for adistortion in a transmission channel based on the estimated transmissionchannel. The channel equalization is optional. The MISO decoder (139700)performs MISO decoding on data outputted from the channel estimator(139600-0).

When MISO decoding is performed on MISO PLP data and L1 signaling data,the MISO decoder (139700) of the present invention may perform 4different operations. Each operation will hereinafter be described.

First of all, when the channel estimators (139600-0, 139600-1) includedin the first receiving unit and the second receiving unit do not performchannel equalization on the MISO PLP, the MISO decoder (139700) mayapply a channel estimation effect on all reference points that can betransmitted, thereby being capable of calculating the LLR value.Accordingly, the same effect as channel equalization may be gained.

Secondly, the MISO decoder (139700) may perform the following operationsin accordance with the operations of the constellation mapper, which isincluded in the BICM module of the broadcasting signal transmitter. Forexample, when the constellation of the constellation map is rotated by apredetermined angle, and when only the Q-phase element of theconstellation is delayed by an arbitrary value, the MISO decoder(139700) may delay only the I-phase element of the constellation by anarbitrary value and may calculate the 20-LLR value based upon theconstellation rotation angle.

According to another embodiment of the present invention, when theconstellation mapper does not rotate the constellation, and when onlythe Q-phase element of the constellation is not delayed by the arbitraryvalue, the MISO decoder (139700) may be capable of calculating the2D-LLR value based upon a normal QAM.

Thirdly, the MISO decoder (139700) may select a MISO decoding matrix, sothat an inverse process of the MISO encoder, which is included in theOFDM generator described in FIG. 21, can be performed in accordance withthe MISO encoding matrix used by the MISO encoder. And, then, the MISOdecoder (139700) may perform MISO decoding.

Finally, the MISO decoder (139700) may merge the MISO PLP data, whichare received through 2 reception antennae. The signal merging methodaccording to the present invention may include maximum ratio combining,equal gain combining, selective combining, and so on. In this case, theMISO decoder (139700) may maximize the SNR of the merged signal, so asto gain a diversity effect.

Additionally, the MISO decoder (139700) may perform MISO decoding on asignal, which is processed with signal merging. Then, after performingMISO decoding on the input of the two antennae, the MISO decoder(139700) may merge the MISO decoded signals.

The MISO decoder (139700) may perform MIMO decoding on the MIMO PLPdata, which are being inputted through the first path and the secondpath. In this case, the MISO decoder (139700) may perform the sameoperations as the above-described MISO decoding process. However, amongthe 4 operation steps, the last operation, i.e., the signal mergingoperation may not be performed.

FIG. 28 illustrates an exemplary structure of any one of the P1 symboldetectors (139200-0, 139200-1) according to an embodiment of the presentinvention. Herein, the P1 symbol detectors (139200-0, 139200-1) may alsobe referred to as a C-A-B preamble detector.

The present invention will describe the P1 symbol detector (139200-0) ofthe first receiving unit. An operation description of the P1 symboldetector (139200-1) of the second receiving unit refers to that of theP1 symbol detector (139200-0) of the first receiving unit.

More specifically, the signal that is converted to a digital signal fromthe ADC (139100-0) may be inputted to a down shifter (139801), a 1^(st)conjugator (139803), and a 2^(nd) delayer (139806) of the P1 symboldetector (139200).

The down shifter (139801) performs inverse modulation by multiplyinge^(−j2πf) ^(SH) ^(t) by the input signal. When inverse modulation isperformed by the down shifter (139801), the signal beingfrequency-shifted and inputted is recovered to the original signal. Theinverse modulated signal may be outputted to a 1^(st) delayer (139802)and a 2^(nd) conjugator (139807).

The 1^(st) delayer (139802) delays the inverse-modulated signal by alength of part C (T_(C)) and then outputs the delayed signal to the1^(st) conjugator (139803). The 1^(st) conjugator (139803) performscomplex-conjugation on the signal, which is delayed by a length of partC (T_(C)). Then, the 1^(st) conjugator (139803) multiplies the inputsignal by the complex-conjugated signal, thereby outputting theprocessed signal to a 1^(st) filter (139804). The 1^(st) filter (139804)uses a running average filter having the length of T_(R)=T_(A), so as toremove (or eliminate) any excessively and unnecessarily remainingmodulation elements, thereby outputting the processed signal to a 3^(rd)delayer (139805). The 3^(rd) delayer (139805) delays the filtered signalby a length of part A (i.e., effective (or valid) symbol) (T_(A)), so asto output the delayed signal to a multiplier (139809).

The 2^(nd) delayer (139806) delays the input signal by a length of partB (T_(B)) and then outputs the delayed signal to the 2^(nd) conjugator(139807). The 2^(nd) conjugator (139807) performs complex-conjugation onthe signal, which is delayed by a length of part B (T_(B)). Then, the2^(nd) conjugator (139807) multiplies the complex-conjugated signal byan inverse-modulated signal, thereby outputting the processed signal toa 2^(nd) filter (139808). The 2^(nd) filter (139808) uses a runningaverage filter having the length of T_(R)=T_(A), so as to remove (oreliminate) any excessively and unnecessarily remaining modulationelements, thereby outputting the processed signal to the multiplier(139809).

The multiplier (139809) multiplies the output of the 2^(nd) filter(139809) by a signal, which is delayed by a length of part A (T_(A)).Thus, a P1 symbol may be detected from each signal frame of the receivedbroadcast signal.

Herein, the length of part C (T_(C)) and the length of part B (T_(B))may be obtained by applying Equation 11 shown above.

FIG. 29 illustrates an exemplary structure of any one of the AP1 symboldetectors (139250-0, 139250-1) according to an embodiment of the presentinvention. Herein, the AP1 symbol detectors (139250-0, 139250-1) mayalso be referred to as an F-D-E preamble detector.

The present invention will describe the AP1 symbol detector (139250-0)of the first receiving unit. An operation description of the AP1 symboldetector (139250-1) of the second receiving unit refers to that of theAP1 symbol detector (139250-0) of the first receiving unit.

More specifically, the signal that is converted to a digital signal fromthe ADC (139100-0) or a signal that is outputted from the P1 symboldetector (139200) may be inputted to an up-shifter (139901), a 1^(st)conjugator (139903), and a 2^(nd) delayer (139906) of the AP1 symboldetector (139250-0).

The up-shifter (139901) performs inverse modulation by multiplyinge^(j2πf) ^(SH) ^(t) by the input signal. When inverse modulation isperformed by the up-shifter (139901), the signal being frequency-shiftedand inputted is recovered to the original signal. More specifically, theup-shifter (139901) of FIG. 29 has the same structure as thedown-shifter (139801) of the P1 symbol detector (139200). However, thefrequency direction of each inverse modulation process is completelyopposite to one another. The signal that is inverse modulated by theup-shifter (139901) may be outputted to a 1^(st) delayer (139902) and a2^(nd) conjugator (139907).

The 1^(st) delayer (139902) delays the inverse-modulated signal by alength of part F (T_(F)) and then outputs the delayed signal to the1^(st) conjugator (139903). The 1^(st) conjugator (139903) performscomplex-conjugation on the signal, which is delayed by a length of partF (T_(F)). Then, the 1^(st) conjugator (139903) multiplies the inputsignal by the complex-conjugated signal, thereby outputting theprocessed signal to a 1^(st) filter (139904). The 1^(st) filter (139904)uses a running average filter having the length of T_(R)=T_(D), so as toremove (or eliminate) any excessively and unnecessarily remainingmodulation elements, thereby outputting the processed signal to a 3^(rd)delayer (139905). The 3^(rd) delayer (139905) delays the filtered signalby a length of part D (i.e., effective (or valid) symbol) (T_(D)), so asto output the delayed signal to a multiplier (139909).

The 2^(nd) delayer (139906) delays the input signal by a length of partE (T_(E)) and then outputs the delayed signal to the 2^(nd) conjugator(139907). The 2^(nd) conjugator (139907) performs complex-conjugation onthe signal, which is delayed by a length of part E (T_(E)). Then, the2^(nd) conjugator (139907) multiplies the complex-conjugated signal byan inverse-modulated signal, thereby outputting the processed signal toa 2^(nd) filter (139908). The 2^(nd) filter (139908) uses a runningaverage filter having the length of T_(R)=T_(D), so as to remove (oreliminate) any excessively and unnecessarily remaining modulationelements, thereby outputting the processed signal to the multiplier(139909).

The multiplier (139909) multiplies the output of the 2^(nd) filter(139909) by a signal, which is delayed by a length of part D (T_(D)).Thus, an AP1 symbol may be detected from each signal frame of thereceived broadcast signal. Herein, the length of part F (T_(F)) and thelength of part E (T_(E)) may be obtained by applying Equation 11 shownabove.

FIG. 30 illustrates an exemplary frame demapper (138200) of thebroadcasting signal receiving apparatus according to an embodiment ofthe present invention, which is adequate for processing an output of theOFDM demodulator shown in FIG. 27.

According to the embodiment of the present invention, the frame demapper(138200) performs an inverse process of the frame builder (100300) ofthe broadcasting signal transmitting apparatus shown in FIG. 20.

The frame demapper of FIG. 30 may include a first frame demapping block(140100) for processing data being inputted through a first path and asecond frame demapping block (140200) for processing data being inputtedthrough a second path.

The first frame demapping block (140100) may include a first frequencydeinterleaver (140101), a first cell demapper (140102), a first coupler(140103), a second coupler (140104), and a third coupler (140105), andthe second frame demapping block (140200) may include a second frequencydeinterleaver (140201) and a second cell demapper (140202).

Also, the first frequency deinterleaver (140101) and the first celldemapper (140102) and the second frequency deinterleaver (140201) andthe second cell demapper (140202) may perform the same operations withrespect to the first path and the second path or may perform independentoperations.

Hereinafter, a data processing method of the blocks included in a firstframe builder demapping block (140100) and a second frame builderdemapping block (140200) will be described in detail.

The first frequency deinterleaver (140101) and the second frequencydeinterleaver (140201) may each perform cell unit deinterleaving in afrequency domain on data being inputted through the first path and thesecond path.

The first cell demapper (140102) and the second cell demapper (140202)may extract common PLP data, PLP data, and L1 signaling data from thedeinterleaved data in cell units. The extracted PLP data may includeMISO-decoded MISO PLP data and MIMO-decoded MIMO PLP data, and theextracted L1 signaling data may include information on the currenttransmission frame and the next transmission frame. Furthermore, whensub-slicing has been performed on the PLP data by the transmitter, asub-slicing processor of the first cell demapper (140102) and the secondcell demapper (140202) may merge the sliced PLP data, thereby mergingthe sliced data so as to generate a single stream.

When the MISO decoder of the OFDM modulator does not perform signalcoupling of the MISO-decoded MISO PLP data, the first coupler (140103)may perform signal coupling of the MISO-decoded MISO PLP data.

The second coupler (140104) and the third coupler (140105) perform thesame functions as the first coupler (140103). However, the differenceherein is that the operations are respectively performed on theL1-pre-signaling data and the L1-post-signaling data.

As shown in FIG. 30, data being processed with frame demapping, i.e.,data being outputted through the first path, such as the MISO PLP data,the MIMO PLP data, and the signaling data may be inputted to the BICMdecoder through a path starting from SRx_k to SRx_post, and the MIMO PLPdata being outputted through the second path may be inputted to the BICMdecoder through a path starting from SRx_m+1 to SRx_n+1.

FIG. 31 illustrates an exemplary BICM decoder of the broadcasting signalreceiving apparatus according to an embodiment of the present invention,which is adequate for processing the output of the frame demapper shownin FIG. 30. Most particularly, according to the embodiment of thepresent invention, the BICM decoder performs an inverse process of theMICM module of the broadcasting signal transmitting apparatus shown inFIG. 19.

The BICM decoder of FIG. 31 includes a first BICM decoding block(150100) receiving MISO PLP data through one path (SRx_k) and processingthe received data, a second BICM decoding block (150300) receiving MIMOPLP data through two paths (SRx_m, SRx_m+1) and processing the receiveddata, and a third BICM decoding block (150500) receiving L1 signalingdata through two paths (SRx_pre, SRx_post) and processing the receiveddata. Also, the third BICM decoding block (150500) includes a firstdecoding block for processing L1-pre-signaling data and a seconddecoding block for processing L1-post-signaling data

Herein, according to the embodiment of the present invention, the MISOPLP data and the L1 signaling data may be inputted after beingMISO-decoded by the OFDM demodulator of FIG. 30, and the MIMO PLP datamay be MIMO-decoded by the BICM decoder of FIG. 31.

More specifically, the BICM decoder of the present invention mayindependently apply the MISO method on the data being inputted from eachpath, and may also apply the MIMO method.

Hereinafter, the data processing method of each block will be described.

First of all, a first BICM decoding block (150100) may include a timedeinterleaver (150101), a cell deinterleaver (150102), a constellationdemapper (150103), a mux (150104), a bit deinterleaver (150105), and anFEC decoder (150106).

The time deinterleaver (150101) performs deinterleaving in a time domainon the inputted data, which MISO-decoded by the OFDM modulator, so as torecover the data to the initial position, and the cell deinterleaver(150102) may perform cell unit deinterleaving on the time-deinterleaveddata.

The constellation demapper (150103) may perform the following functionsin accordance with the operations of the MISO decoder (139700) of theOFDM demodulator.

First of all, in case the MISO decoder (139700) performs onlyMISO-decoding without directly outputting the LLR value, theconstellation demapper (150103) may calculate the LLR value. Morespecifically, a detailed description will hereinafter be made. Whenconstellation rotation and Q-phase element delay are performed by theconstellation demapper, which is included in the BICM module of thebroadcasting signal transmitting apparatus shown in FIG. 19, theconstellation demapper (150103) may first delay an I-phase element andmay then calculate the LLR value. If the constellation demapper, whichis included in the BICM module of the broadcasting signal transmittingapparatus, does not perform constellation rotation and Q-phase elementdelay, the constellation demapper (150103) may calculate an LLR valuebased upon a normal QAM standard.

The method for calculating the LLR value may include a method forcalculating a 2-D LLR and a method for calculating a 1-D LLR value. Incase of calculating the 1-D LLR value, any one of the input to the firstpath and the input to the second path is performed, so as to reduce thecomplexity in the LLR calculation.

The mux (150104) may recover the demapped data to a bit stream format.More specifically, when the output order of the bits are adjusted (orcontrolled) and transmitted from the demux of the transmitting end, themux (150104) recovers the initial output order.

The bit deinterleaver (150105) performs deinterleaving on the inputtedbit stream in bit units, and the FEC decoder (150106) performsFEC-decoding on the data processed with bit-deinterleaving, so as toperform error correction over the transmission channel, therebyoutputting the MISO PLP data. In this case, according to the embodimentof the present invention, LDPC decoding and/or BCH decoding method(s)may be used as the decoding method.

The second BICM decoding block (150300) may include a first timedeinterleaver (150301) and a second time deinterleaver (150401), a firstcell deinterleaver (150302) and a second cell deinterleaver (150402), afirst constellation demapper (150303) and a second constellationdemapper (150403), a mux (150305), a bit deinterleaver (150306), and anFEC decoder (150307).

The first time deinterleaver (150301) and the second time deinterleaver(150401) may perform deinterleaving in a time domain on the inputteddata in cell units, so as to recover data by the initial (or original)data order. In this case, the first cell deinterleaver (150302) and thesecond cell deinterleaver (150402) may perform cell deinterleaving onlyon the data corresponding to half the size of a cell included in an FECblock, among the data being inputted through each path. Eventually, thecell deinterleaving performed by the first cell deinterleaver (150302)and the second cell deinterleaver (150402) may have the same effect asthe deinterleaving performed by the MISO type cell deinterleaver(150102) by using one FEC block.

The MIMO decoder (150303) performs MIMO decoding on the data beingoutputted from the first and second cell deinterleavers (150302,150402). Among the 4 different operations of the MISO decoder (139700),which is included in the OFDM demodulator shown in FIG. 27, the MIMOdecoder (150303) may identically perform the 3 remaining operations ofthe MISO decoder (139700) excluding the fourth operation, i.e., thesignal coupling operation. At this point, the MIMO decoder (150303) mayalso perform decoding by using the MIMO encoding matrix according to thefirst to third embodiments of the present invention.

For the description of the first constellation demapper (150304), thesecond constellation demapper (150404), the mux (150305), the bitdeinterleaver (150306), and the FEC decoder (150307), reference may bemade to the operations of the same blocks included in the first BICMdecoding block (150100).

The third BICM decoding block (150500) includes a first decoding blockfor processing L1-pre-signaling data and a second decoding block forprocessing L1-post-signaling data.

At this point, the L1-pre-signaling data and the L1-post-signaling dataare MISO decoded by the MISO decoder (139700) of the OFDM demodulatorshown in FIG. 27.

The first decoding block may include a time deinterleaver (150501), acell deinterleaver (150502), a constellation demapper (150503), and anFEC decoder (150504), and the second decoding block may include a timedeinterleaver (150601), a cell deinterleaver (150602), a constellationdemapper (150603), a mux (150604), a bit deinterleaver (150605), and anFEC decoder (150606).

Hereinafter, since the functions of each block included in the firstdecoding block and the second decoding block are identical to therespective blocks included in the first BICM decoding block (150100), adetailed description of the same will be omitted. However, according toan embodiment of the present invention, each of the FEC decoders(150504, 150606) shall perform FEC decoding, after performingde-shortening and de-puncturing on the input data.

Eventually, the first BICM decoding block (150100) may output theBICM-decoded MISO PLP data to the output processor, and the second BICMdecoding block (150300) may output the BICM-decoded MIMO PLP data to theoutput processor. Also, the first decoding block of the third BICMdecoding block (150500) may also Output the BICM-decodedL1-pre-signaling data to the output processor, and the second decodingblock of the third BICM decoding block (150500) may also output theBICM-decoded L1-post-signaling data to the output processor.

Since the BICM decoder of FIG. 31 is positioned between the first andsecond cell deinterleavers (150302, 150402) and the first and secondconstellation demappers (150304, 150404), by performing MIMO decodingafter performing both the time deinterleaving and cell deinterleavingprocesses is symbol units, the complexity in the memory of thebroadcasting signal recover may be reduced.

According to another embodiment of the present invention, the MIMOdecoder of the second BICM decoding block (150300) may also bepositioned before the first and second time deinterleavers (150301,150401).

FIG. 32 illustrates an OFDM demodulator (138100) of a broadcastingsignal receiving apparatus according to another embodiment of thepresent invention. The OFDM demodulator of FIG. 32 corresponds to anOFDM demodulator performing inverse operation processes of the OFDMgenerator shown in FIG. 24. According to the embodiment of the presentinvention, in order to receive broadcasting signals that are transmittedby using the MISO or MIMO method, two reception antennae (Rx1, Rx2) areused. According to the embodiment of the present invention, the presentinvention uses a polarity multiplexing MIMO method.

The OFDM demodulator (138100) of FIG. 32 includes a first receiving unit(160100) performing OFDM demodulation on a signal, which is receivedthrough a first reception antenna (Rx1), and a second receiving unit(160300) performing OFDM demodulation on a signal, which is receivedthrough a second reception antenna (Rx2).

According to the embodiment of the present invention, the firstreceiving unit (160100) includes a tuner (160101), an ADC (160102), a P1symbol detector (160103), an AP1 symbol detector (160104), atime/frequency synchronization unit (160105), a GI remover (160106), anFFT module (160107), and a channel estimator (160108). According to theembodiment of the present invention, the second receiving unit (160300)includes a tuner (160301), an ADC (160302), a P1 symbol detector(160303), an AP1 symbol detector (160304), a time/frequencysynchronization unit (160305), GI remover (160306), an FFT module(160307), and a channel estimator (160308).

The OFDM demodulator of FIG. 32 does not include an MISO decoder, andthe OFDM demodulator of FIG. 27 includes an MISO decoder. With theexception of such differences, the two OFDM demodulators are identicalto one another. Therefore, for the detailed description of theoperations performed by each block shown in FIG. 32, reference may bemade to the description on the operations of the same blocks shown inFIG. 27. Accordingly, detailed description of the corresponding blockswill be omitted for simplicity. Additionally, according to theembodiment of the present invention, the P1 symbol detector (160103)detects the P1 symbol by using FIG. 28, and the AP1 symbol detector(160104) detects the AP1 symbol by using FIG. 29. In this case, MISO PLPdata that are not processed with MISO decoding and MIMO PLP data thatare not processed with MIMO decoding are outputted to the BICM decoder.

FIG. 33 illustrates a frame demapper (138200) of a broadcasting signalreceiving apparatus according to another embodiment of the presentinvention, which is adequate for processing the output of the OFDMdemodulator shown in FIG. 32.

According to the embodiment of the present invention, the frame demapper(138200) performs inverse operation processes of the frame builder(100300) included in the broadcasting signal transmitting apparatusshown in FIG. 23.

The frame demapper of FIG. 33 includes a first frame demapping block(170100) for processing data that are inputted through a first path, anda second frame demapping block (170300) for processing data that areinputted through a second path. The first frame demapping block (170100)includes a first pair-wise frequency deinterleaver (170101) and a firstpair-wise cell demapper (170102), and the second frame demapping block(170300) includes a second pair-wise frequency deinterleaver (170301)and a second pair-wise cell demapper (170302).

Additionally, the first pair-wise frequency deinterleaver (170101) andthe first pair-wise cell demapper (170102) and the second pair-wisefrequency deinterleaver (170301) and the second pair-wise cell demapper(170302) may perform the same operations with respect to the first pathand the second path and may also independently perform the respectiveoperations.

The data processing method of the blocks included in each of the firstframe builder demapping block (170100) and the second frame builderdemapping block (170300) will hereinafter be described in detail.

The first pair-wise frequency deinterleaver (170101) and the secondpair-wise frequency deinterleaver (170301) performs deinterleaving onthe data being respectively inputted through the first path and thesecond path in cell units and in the respective frequency domain. Inthis case, the first pair-wise frequency deinterleaver (170101) and thesecond pair-wise frequency deinterleaver (170301) groups 2 consecutivecells in pairs, thereby processing each pair of cells as a singledeinterleaving unit and performing frequency deinterleaving. Thedeinterleaving procedure may be performed as an inverse process of theinterleaving procedure performed by the transmitting unit. And, thefrequency deinterleaved data are recovered by the initial data order,thereby being outputted.

The first pair-wise cell demapper (170102) and the second pair-wise celldemapper (170302) may extract common PLP data, PLP data, and L1signaling information in cell units from the deinterleaved data. Theextracted PLP data may include MISO PLP data, wherein the MISO method isto be applied, and MIMO PLP data, wherein the MIMO method is to beapplied. And, the extracted L1 signaling information may includeinformation on the current transmission frame and information on thenext transmission frame. Additionally, if sub-slicing has been performedon the PLP data by the transmitter, the first pair-wise cell demapper(170102) and the second pair-wise cell demapper (170302) may merge thesub-sliced PLP data, so as to generate a single stream.

Moreover, the first pair-wise cell demapper (170102) and the secondpair-wise cell demapper (170302) may group 2 consecutive cell in pairsand may then perform extraction.

The data being processed with cell demapping by the first pair-wise celldemapper (170102) may be inputted to the BICM decoder through a firstpath (from SRx_0 to SRx_post), and the data being processed with celldemapping by the second pair-wise cell demapper (170302) may beoutputted to the BICM decoder through a second path (from SRx_0+1 toSRx_post+1).

FIG. 34 illustrates a BICM decoder of the broadcasting signal receivingapparatus according to another embodiment of the present invention,which is adequate for processing the output of the frame demapper shownin FIG. 33. Most particularly, according to the embodiment of thepresent invention, the BICM decoder may perform inverse operationprocesses of the BICM Module included in the broadcasting signaltransmitting apparatus shown in FIG. 23.

With the exception of the BICM decoder of FIG. 34 including an MISOdecoder, the BICM decoder of FIG. 34 has the same structure as the BICMdecoder shown in FIG. 31. More specifically, FIG. 34 may independentlyperform MISO decoding or MIMO decoding on the data being inputted fromeach path.

The BICM decoder of FIG. 34 includes a first BICM decoding block(180100) receiving MISO PLP data from 2 paths (SRx_k, SRx_k+1) andprocessing the received MISO PLP data, a second BICM decoding block(180300) receiving MIMO PLP data from 2 paths (SRx_m, SRx_m+1), and athird BICM decoding block (180500) receiving L1 pre-signaling data from2 paths (SRx_pre, SRx_pre+1) and receiving L1 post-signaling data frompaths (SRx_post, SRx_post+1), thereby processing the received data. Inorder to do so, third BICM decoding block (180500) includes a firstdecoding block for processing the L1 pre-signaling data, and a seconddecoding block for processing the L1 post-signaling data. The first BICMdecoding block (180100) includes first and second time deinterleavers(180101, 180201), first and second cell deinterleavers (180102, 180202),a MISO decoder (180103), a constellation demapper (180104), a MUX(180105), a bit deinterleaver (180106), and an FEC decoder (180107).

The second BICM decoding block (180300) includes first and second timedeinterleavers (180301, 180401), first and second cell deinterleavers(180302, 180402), an MISO decoder (180303), a constellation demapper(180304), a MUX (180405), a bit deinterleaver (180306), and an FECdecoder (180307).

The first decoding block of the third BICM decoding block (180500)includes first and second time deinterleavers (180501, 180601), firstand second cell deinterleavers (180502, 180602), an MISO decoder(180503), a constellation demapper (180504), and an FEC decoder(180505).

The second decoding block of the third BICM decoding block (180500)includes first and second time deinterleavers (180701, 180801), firstand second cell deinterleavers (180702, 180802), an MISO decoder(180703), a constellation demapper (180704), a MUX (180705), a bitdeinterleaver (180706), and an FEC decoder (180707). Herein, the MUX ofeach of the first to third decoding blocks (180100, 180300, 180500) mayalso be referred to as a cell-bit MUX.

The MISO decoders (180103, 180503, 180703) according to the presentinvention may perform 4 different operation steps. Hereinafter, eachoperation step will be described in detail.

Firstly, when the channel estimator included in the OFDM demodulatordoes has not performed channel equalization, the MISO decoders (180103,180503, 180703) may calculate an LLR value, after applying a channelestimation effect on all transmittable reference points. Thus, the sameeffect as channel equalization may be gained.

Secondly, the MISO decoders (180103, 180503, 180703) may perform thefollowing operations in accordance with the operations of theconstellation mapper included in the BICM module of the broadcastingsignal transmitting apparatus. When the constellation mapper included inthe BICM module of the broadcasting signal transmitting apparatusrotates the constellation to a predetermined angle and delays only theQ-phase element of the constellation by an arbitrary value, the MISOdecoders (180103, 180503, 180703) may delay only the I-phase element ofthe constellation by an arbitrary value and may calculate a 2D-LLR valuebased upon the constellation rotation angle.

In case the constellation mapper included in the BICM module of thebroadcasting signal transmitter does not rotate the constellation anddoes not delay only the Q-phase element of the constellation by anarbitrary value, the MISO decoder (180103, 180503, 180703) may calculatea 2-D LLR value based upon a normal QAM standard.

Thirdly, the MISO decoders (180103, 180503, 180703) may perform MISOdecoding, after selecting a MISO decoding matrix, so that an inverseprocess of the MISO encoder included in the BICM module of thebroadcasting signal transmitter can be performed with respect with theMISO encoding matrix used by the MISO encoder.

Finally, the MISO decoders (180103, 180503, 180703) may combine thesignals that are inputted through two reception antennae. Examples ofthe signal combining method according to the present invention mayinclude maximum ratio combining, equal gain combining, selectivecombining, and so on. And, by maximizing the SNR of the combinedsignals, a diversity effect may be gained.

Additionally, the MISO decoder (180103, 180503, 180703) may perform MISOdecoding on a signal, which is processed with signal combining, and theMISO decoded signals may be combined after performing MISO decoding onthe two antenna inputs.

The MIMO decoder (180303) performs MIMO decoding on the MIMO PLP data,which are received through 2 paths (SRx_m, SRx_m+1). And, among theabove-described 4 operation processes of the MISO decoder (180103,180503, 180703), with the exception for the fourth operation process,i.e., the signal combining operation, the remaining operation processesmay be performed identically as the MIMO decoder (180303). At thispoint, the MIMO decoder (180303) may perform decoding by using the MIMOencoding matrix used in the first to third embodiments of the presentinvention, which are described above.

For the remaining blocks, reference may be made to the description ofthe operation processes of the respective blocks shown in FIG. 31. And,therefore, detailed description of the same will hereinafter be omittedfor simplicity. More specifically, for the portions that are notdescribed with reference to FIG. 34, the present invention will followthe description on the operation processes shown in FIG. 31.

Eventually, the first BICM decoding block (180100) outputs thedeinterleaved, MISO decoded, and error corrected MISO PLP data to anouter processor, and the second BICM decoding block (180300) outputs thedeinterleaved, MISO decoded, and error corrected MIMO PLP data to anoutput processor. Additionally, the first decoding block of the thirdBICM decoding block (150500) outputs the deinterleaved, MISO decoded,and error corrected L1 pre-signaling data to an output processor, andthe second decoding block outputs deinterleaved, MISO decoded, and errorcorrected L1 post-signaling data to an output processor.

Since the MISO/MIMO decoder is/are located between the celldeinterleaver and the first and second constellation demappers, the BICMdecoder of FIG. 34 may perform MIMO decoding after performing both timedeinterleaving and cell deinterleaving in symbol units. Thus, thecomplexity level in the memory of the broadcasting signal receiver maybe reduced.

According to another embodiment of the present invention, the MISO/MIMOdecoder may be located in front of the time deinterleaver. Morespecifically, in the first BICM decoding block (180100), the MISOdecoder may be located in front of the first and second timedeinterleavers (180101, 180201), and, in the second BICM decoding block(180300), the MIMO decoder may be located in front of the first andsecond time deinterleavers (180301, 180401). Additionally, in the firstdecoding block of the third BICM decoding block (180500), the MISOdecoder may be located in front of the first and second timedeinterleavers (180501, 180601), and, in the second decoding block, theMISO decoder may be located in front of the first and second timedeinterleavers (180701, 180801).

FIG. 35 illustrates an exemplary output processor (138300) of thebroadcasting signal receiving apparatus according to an embodiment ofthe present invention.

FIG. 35 shows an exemplary embodiment of the output processor (138300)corresponding to a case when 1 output stream is used (or when 1 PLPinput is used), wherein the output processor (138300) performs theinverse processes of the input processor (100100) and the inputpre-processor (100000).

When 1 output stream is used, the output processor may include a BBdescrambler (190100), a padding remover (190200), a CRC-8 decoder(190300), and a BB frame processor (190400).

The BB descramble (190100) descrambles the inputted bit stream. Morespecifically, the BB descrambler (190100) performs an XOR operation ofthe bit stream, which is identically generated as the PRBS processed bythe BB scrambler (110500) shown in FIG. 16, and an input bit stream,thereby performing descrambling. When required, the padding remover(190200) removes the padding bit, which is inserted by the broadcastingsignal transmitting apparatus. The CRC-8 decoder (190300) performs CRCdecoding on the inputted bit stream, and the BE frame processor mayfirst decode the information included in the BB frame header. Then, theCRC-8 decoder (190300) may use the decoded information, so as to recoverthe TS/IP/GS stream and output the recovered stream.

FIG. 36 illustrates an exemplary output processor (138300) of thebroadcasting signal receiving apparatus according to another embodimentof the present invention.

FIG. 36 illustrates an example of an output processor (138300) accordingto an embodiment of the present invention corresponding to a case whenmultiple output streams are used, i.e., when multiple PLPs are received.Herein, the output processor shown herein is similar to the inverseprocess of the input processor (100100) of FIG. 17 and FIG. 18 and theinput pre-processor (100000) of FIG. 9. When components configuring aservice are each received by a different PLP, the output processor(138300) of FIG. 36 is adequate for configuring a single service byextracting the components from each PLP.

The output processor include a PLP output processing block forprocessing PLP data and a signaling processing block for processingsignaling data.

The PLP output processing block may include n+1 number of BBdescramblers (193100-0˜n) for processing n number of PLPs, n+1 number ofpadding removers (193200-0˜n), n+1 number of CRC-8 decoders(193300-0˜n), n+1 number of BB frame processors (193400-0˜n), n+1 numberof De-jitter buffers (193500-0˜n), n+1 number of null packet inserters(193600-0˜n), n-m+1 number of in-band signaling decoders (193700-m˜n), aTS clock regenerator (193800), and a TS re-coupler (193900).

If the output stream corresponds to an IP stream or a GSE stream, theCRC-8 decoders (193300-0˜n) and the n+1 number of null packet inserters(193600-0˜n) may be omitted from the block diagram of FIG. 36, or thecorresponding blocks may be bypassed. For example, since the IP packetis buffered to best-fit a time stamp, so as to be reproduced by thereceiver, the transmitter is not required to delay the correspondingdata, and a null packet is not required to be added/deleted.

Since the operations of each of the BB descramblers (193100-0˜n), thepadding removers (193200-0˜n), the CRC-8 decoders (193300-0˜n), and theBB frame processors (193400-0˜n) are identical to the operations of therespective blocks shown in FIG. 35, reference may be made to FIG. 35 forthe detailed description of the corresponding blocks and, therefore,detailed description of the same will be omitted herein. In thedescription of FIG. 36, only the portions that are different from thestructure shown in FIG. 35 will be described herein.

The de-jitter buffers (193500-0˜n) compensates for the delays, which arearbitrarily inserted by the transmitting end for the synchronizationbetween the multiple PLPs, in accordance with a TTO (time to outputparameter).

The null packet inserters (193600-0˜n) may refer to DNP (deleted nullpacket) information, which indicate information on the number of deletednull packets, so as to insert the null packets, which are removed by thetransmitting end, in the respective positions of the corresponding TS.At this point, the TS clock regenerator (193800) may recover detailedtime synchronization of the output packet based upon the ISCR (InputStream Time Reference).

The TS coupler (193900) may also be referred to as a TS merger and, asdescribed above, the TS coupler (193900) may recover the common PLP, anddata PLPs, which are recovered as described above, to the initial TS orIP or GSE stream, and may then output the recovered stream. According tothe present invention, TTO, DNP, ISCR information are all included inthe BB frame header and transmitted. The in-band signaling decoders(193700-m˜n) may recover the in-band signaling information, which isbeing transmitted through the data PLP, and may then output therecovered information.

For example, it will be assumed herein that a service is configured of acommon PLP, a video component PLP, an audio component PLP, and datacomponent PLP, as shown in (b) of FIG. 11, through the inputpre-processor (100000) the input processor (100100) of the transmitter.Accordingly, the de-jitter buffers (193500-0˜n) of FIG. 36 may outputmultiple PLPs to the null packet inserters (193600-0˜n), as shown in (b)of FIG. 11, and the null packet inserters (193600-0˜n) may refer to DNPinformation, so as to insert the null packets, which are removed by thetransmitting end, in the respective positions of the corresponding TS.Accordingly, a common TS, a video component TS, an audio component TS,and a data component TS, each having the null packets inserted therein,as shown in (a) of FIG. 11 ((b) of FIG. 10), may be outputted to the TScoupler (193900). When the TS coupler (193900) merges the valid packetsof the common TS, the video component TS, the audio component TS, andthe data component TS, a TS configuring a singled service may beoutputted, as shown in (a) of FIG. 10.

Meanwhile, the signaling output processing block may include two BBdescramblers (194100, 194200) and an L1 signaling decoder (194300). TheBB descrambler (194100) may descramble data corresponding toL1-pre-signaling information and the BB descrambler (194200) maydescramble data corresponding to L1-post-signaling information.Moreover, data corresponding to L1 signaling information may bedescrambled in a single BB descrambler.

The L1 signaling decoder (194300) decodes the descrambledL1-pre-signaling information and L1-post-signaling information, so as torecover the L1 signaling information. The recovered L1 signalinginformation includes L1-pre-signaling information and L1-post-signalinginformation. Additionally, the L1-post-signaling information includesconfigurable L1-post-signaling information and dynamic L1-post-signalinginformation.

The L1 signaling information, which is recovered by the L1 signalingdecoder (194300) may be delivered to the system controller, so as toprovide parameters, which are required by the broadcasting signalreceiver for performing operations, such as BICM (Bit Interleaved Codingand Modulation) decoding, frame demapping, OFDM (Orthogonal FrequencyDivision Multiplex) demodulation, and so on.

FIG. 37 illustrates a block diagram showing a structure of abroadcasting signal receiving apparatus according to yet anotherembodiment of the present invention. Herein, FIG. 37 corresponds to ablock diagram showing the structure of the broadcasting signal receivingapparatus, when the stream type being inputted to the inputpre-processor of the transmitter corresponds to the TS format. In caseof receiving each of the components configuring a single service througha different PLP, the broadcasting signal receiving apparatus of FIG. 37is adequate for extracting the components from each PLP, therebyconfiguring a single service.

In FIG. 37, for the detailed description on the operations of the OFDMdemodulator (210100) and the frame demapper (210200), reference may bemade to the detailed description on the operations of theabove-described OFDM demodulator (138100) and frame demapper (138200),and, therefore, detailed description of the same will be omitted herein.

In FIG. 37, the multiple PLP deinterleaving and demodulator modules(210500), which perform deinterleaving and demodulation on each of themultiple PLPs, perform similar operations as the above-described BICMdecoder (138300). And, multiple BBF decoders and null packetreconstruction modules (210600), which output TS by performing BBF(BaseBand Frame) decoding and null packet reconstruction operations, andthe TS merger (210700) perform operations that are similar to theoperations of the above-described output processor (138400). The L1decoder (210300) corresponds to the above-described L1 signalingdecoder.

In FIG. 37, when a service is selected, the PLP selecting module(210400) controls the frame demapper (210200), so that only the PLP ofthe components configuring the selected service can be outputted fromthe frame demapper (210200). Herein, the service selection may berealized by a user's request, or may be automatically realized in thesystem.

More specifically, the OFDM demodulator (210100) decodes the P1/AP1signaling information, and the L1 decoder (210600) decodes L1/L2signaling information, so as to acquire information on a transmissionframe structure and information on PLP configuration. According to anembodiment of the present invention, the components configuring aservice are received by multiple PLPs. In this case, since PLPinformation or service information on the component structure isincluded in the L1 signaling information, the broadcasting receiver maybe capable of knowing to which PLPs the components, which configure aservice, are included.

Accordingly, when a service is selected, the PLP selecting module(210400) controls the frame demapper (210200), and the frame demapper(210200) outputs multiple sets of PLP data including the correspondingcomponents to the selected service. The multiple sets of PLP data areprocessed with deinterleaving/demodulation processes by thecorresponding deinterleaving and demodulator module. And, after the BBFdecoding/null packet reconstruction processes are processed by the BBFdecoder and null packet reconstruction module, the TS merger (210700)merges the processed data to configure a TS respective to the selectedservice.

For example, it will be assumed herein that a service is configured of acommon PLP, a video component PLP, an audio component PLP, and datacomponent PLP, as shown in (b) of FIG. 11, through the inputpre-processor (100000) the input processor (100100) of the transmitter.Accordingly, the BBF decoders of FIG. 37 may output multiple PLPs to thenull packet reconstruction modules, as shown in (b) of FIG. 11, and thenull packet reconstruction modules may refer to DNP information, so asto insert the null packets, which are removed by the transmitting end,in the respective positions of the corresponding TS. Accordingly, acommon TS, a video component TS, an audio component TS, and a datacomponent TS, each having the null packets inserted therein, as shown in(a) of FIG. 11 ((b) of FIG. 10), may be outputted to the TS merger(210700). When the TS merger (210700) merges the valid packets of thecommon TS, the video component TS, the audio component TS, and the datacomponent TS, a TS configuring a singled service may be outputted, asshown in (a) of FIG. 10.

FIG. 38 illustrates a block diagram showing a structure of thebroadcasting signal receiving apparatus according to yet anotherembodiment of the present invention. Herein, FIG. 38 corresponds to ablock diagram showing the structure of the broadcasting signal receivingapparatus, when a stream type inputted to the input pre-processor of thetransmitter correspond to an IP stream format or a GSE stream format.The broadcasting signal receiving apparatus of FIG. 38 is adequate forconfiguring a service, by extracting components from each PLP, when thecomponents configuring a service are included in each PLP.

The broadcasting signal receiving apparatus of FIG. 38 may include anOFDM demodulator (220100), a frame demapper (220200), an L1 decoder(220300), a PLP selecting module (220400), multiple PLP deinterleavingand demodulator module (220500), multiple FBI decoder (220600), and abuffer unit (220700). The buffer unit (220700) may include a PSI/SI (IPservice information) buffer, a bootstrap buffer, a metadata buffer, anaudio buffer, a video buffer, and a data buffer depending upon the datatype.

For the detailed description on the operations of the OFDM demodulator(220100) and the frame demapper (220200) shown in FIG. 38, reference maybe made to the detailed description on the operations of theabove-described OFDM demodulator (138100) and frame demapper (138200),and, therefore, detailed description of the same will be omitted herein.

The multiple PLP deinterleaving and demodulator module (220500)performing deinterleaving and demodulation on each of the multiple PLPsin FIG. 38 performs operations that are similar to the operations of theabove-described BICM decoder (138300), and the multiple BBF decoders(220600), which perform BBF decoding on each of the multiple PLPs, so asto output an IP stream, also perform operations that are similar to theoperations of the above-described output processor (138400). The L1decoder (220300) corresponds to the above-described L1 signalingdecoder.

In FIG. 38, when a service is selected, the PLP selecting module(220400) controls the frame demapper (220200) so that only the PLPs ofthe components configuring the selected service can be outputted fromthe frame demapper (220200). Herein, the service selection may berealized by a user's request, or may be automatically realized in thesystem.

More specifically, the OFDM demodulator (220100) decodes the P1/AP1signaling information, and the L1 decoder (220600) decodes L1/L2signaling information, so as to acquire information on a transmissionframe structure and information on PLP configuration. According to anembodiment of the present invention, the components configuring aservice are received by multiple PLPs. In this case, since PLPinformation or service information on the component structure isincluded in the L1 signaling information, the broadcasting receiver maybe capable of knowing to which PLPs the components, which configure aservice, are included.

Accordingly, when a service is selected, the PLP selecting module(220400) controls the frame demapper (220200), and the frame demapper(220200) outputs multiple sets of PLP data including the correspondingcomponents to the selected service. The multiple sets of PLP data areprocessed with deinterleaving/demodulation processes by thecorresponding deinterleaving and demodulator module. And, after the BBFdecoding process is processed by the BBF decoder, the processed data areoutputted to the corresponding buffer, among a PSI/SI (IP serviceinformation) buffer, a bootstrap buffer, a metadata buffer, an audiobuffer, a video buffer, and a data buffer of the buffer unit (220700) bya switching process. Then, the PSI/SI (IP service information) buffer,the bootstrap buffer, the metadata buffer, the audio buffer, the videobuffer, and the data buffer may temporarily store PLP data, which areinputted from any one of the multiple BBF decoders (220600), therebyoutputting the stored PLP data. The present invention may furtherinclude a stream merger and a component splitter between the multipleBBF decoders (220600) and the buffer unit (220700).

More specifically, an IP stream of the multiple sets of PLP data, whichare BBF decoded and outputted from the multiple BBF decoders (220600)corresponding to the components of the selected service, after beingprocessed with BBF decoding by the multiple BBF decoders (220600), maybe merged by the stream merger, so as to be outputted as a single IPstream corresponding to the selected service. At this point, the streammerger may refer to an IP address and a UDP port number, so as to mergethe multiple IP streams to a single IP stream corresponding to a singleservice.

The component splitter may divide (or separate) the data included in theIP stream, which is merged to a service and outputted by the streammerger, for each component, and may then output the data for eachcomponent to the buffer unit (220700). The component splitter may useaddress information, such as the IP address and the UDP port number, soas to switch to a buffer corresponding to each component included in thebuffer unit, thereby outputting the data corresponding to eachcomponent. The buffer unit (220700) may buffer the data corresponding toeach component in accordance with the output order of the IP stream.

Meanwhile, according to the embodiment of the present invention, atleast one of the components configuring a service may be divided into abase layer and an enhancement layer and then may be transmitted.

According to the embodiment of the present invention, by encoding videocomponent by using the SVC method, the component may be divided intobase layer data and enhancement layer data. The base layer datacorrespond to data for images having basic picture quality. Herein,although the base layer data are robust against the communicationenvironment, the picture quality of the base layer data is relativelylow. And, the enhancement layer data correspond to additional data forimages having higher picture quality. And, although the enhancementlayer data can provide high picture quality images, the enhancementlayer data are more or less resilient to the communication environment.

In the present invention, video data for terrestrial broadcasting may bedivided into base layer data and enhancement layer data. And, in orderto allow the video data for mobile broadcasting to flexibly respond tothe mobile broadcasting communication environment, the video data formobile broadcasting may be divided into base layer data and enhancementlayer data. The receiver may receive and decode only the base layervideo data, so as to acquire images having basic image quality. And, thereceiver may also receive and decode both the base layer video data andthe enhancement layer video data, so as to acquire images having ahigher picture quality. For example, the mobile receiver, such as amobile phone, a movable TV, and so on, may decode only the base layerdata, so as to provide images having basic picture quality, and afixed-type receiver, such as a general household TV, may decode both thebase layer data and the enhancement layer data, so as to provide imageshaving high picture quality.

At this point, the base layer data and the enhancement layer data may betransmitted through a single PLP, or may be transmitted throughdifferent PLPs.

FIG. 39 illustrates a block diagram showing the process of thebroadcasting signal receiver for receiving a PLP best fitting itspurpose according to an embodiment of the present invention.

FIG. 39 shows an example of receiving a transmission frame, whichincludes a service configured of multiple PLPs, i.e., PLP1 to PLP4.

Herein, it will be assumed that PLP1 transmits SVC encoded base layerdata, that PLP2 transmits SVC encoded enhancement layer data, that PLP3transmits an audio stream, and that PLP4 transmits a data stream.

In the present invention, by adjusting and controlling the physicalparameters in accordance with the characteristics of the data includedin each PLP, the mobile reception performance or data communicationperformance may be differently set up, so that the receiver canselectively receive the required PLPs based upon the characteristics ofreceiver. Hereinafter, a detailed example will be described.

As shown in FIG. 39, since the PLP1 transmitting the base layer datashould be capable of being received by a general fixed-type receiver aswell as a mobile receiver, the broadcasting signal transmittingapparatus may set up physical parameters for ensuring high receptionperformance respective to PLP1 and may then transmit the set upparameters.

Additionally, the PLP2 transmitting the enhancement layer data have alower reception performance as compared to the PLP1. Accordingly, evenif the mobile receiver is incapable of receiving PLP2, in order to allowa fixed-type receiver, which is required to receive high picture qualitybroadcasting programs having high resolution, the broadcasting signaltransmitting apparatus may set up and transmit physical parameters ofPLP2.

Accordingly, as shown in FIG. 39, the mobile receiver may decode PLP1transmitting a video stream of the base layer, and may decode PLP3 andPLP4 transmitting audio and data streams, so as to provide a servicehaving general (or standard) resolution.

Alternatively, the fixed-type receiver may decode all of PLP1transmitting a video stream of the base layer, PLP2 transmitting a videostream of the enhancement layer, and PLP3 and PLP4 transmitting audioand data streams, so as to provide a service having high picturequality.

However, this is merely exemplary, and, therefore, the mobile receivermay also decode all of PLP1 transmitting a video stream of the baselayer, PLP2 transmitting a video stream of the enhancement layer, PLP3transmitting an audio stream, and PLP4 transmitting a data stream, so asto provide a service having high picture quality.

Meanwhile, according to an embodiment of the present invention, afterperforming SVC decoding on the video data, the broadcasting signaltransmitting apparatus according to the present invention may transmitbase layer data by using a non-MIMO method, and the broadcasting signaltransmitting apparatus may transmit enhancement layer data by using aMIMO method. In the present invention, a broadcasting signaltransmitting system supporting the MIMO method will be referred to as aMIMO transmitting system.

Hereinafter, diverse embodiments of the MIMO transmitting system usingSVC will be described in detail.

FIG. 40 illustrates a MIMO transmission system using an SVC and abroadcast signal transmitting method according to an embodiment of thepresent invention.

As shown in FIG. 40, the MIMO transmitting system may include an SVCencoder (244100), which encodes broadcasting data by using the SVCmethod, and a MIMO encoder (244200), which distributes data by using aspatial diversity or spatial multiplexing method, so that the data canbe transmitted to multiple antennae. Hereinafter, the MIMO encoder mayalso be referred to as a MIMO processor.

FIG. 40 shows an exemplary broadcast signal transmitting apparatus,which uses a Hierarchical modulation method.

The SVC encoder (244100) performs SVC encoding on the broadcast data andoutputs the SVC-encoded data as the base layer data and the enhancementlayer data. The base layer data are equally transmitted from a 1^(st)transmission antenna (Tx1; 244300) and a 2^(nd) transmission antenna(Tx2; 244400). And, the enhancement layer data are processed with MIMOencoding by the MIMO encoder (244200), thereby being respectivelyoutputted through the 1^(st) transmission antenna (244300) and the2^(nd) transmission antenna (244400) as identical data or as differentdata. In this case, the constellation mapper of the transmitting systemperform symbol mapping on the corresponding symbol in accordance withthe modulation type, as shown on the left-side drawing. For example, theconstellation mapper may perform layer modulation, so as to map bitscorresponding to the base layer to an MSB (Most Significant Bit) portionof the corresponding symbol, and to map bits corresponds to theenhancement layer to an LSB (Least Significant Bit) portion of thecorresponding symbol.

The receiving system may use a constellation demapper, so as to separatethe base layer data and the enhancement layer data from the demodulatedbit information and to acquire the separated data. The enhancement layerdata may be processed with MIMO decoding, so as to be acquired by usingbit information of a final SVC. In case the bit informationcorresponding to the MIMO cannot be separated, the receiver may use onlythe bit information corresponding to the SISO or the MISO, so as toacquire the base layer data and to provide the respective service.

FIG. 41 illustrates a MIMO transmission system using an SVC and abroadcast signal transmitting method according to another embodiment ofthe present invention.

As shown in FIG. 41, the MIMO transmitting system may include an SVCencoder (245100), which encodes broadcasting data by using the SVCmethod, and a MIMO encoder (245200), which distributes data by using aspatial diversity or spatial multiplexing method, so that the data canbe transmitted to multiple antennae. FIG. 41 illustrates an exemplarytransmitting system using a hybrid modulation method or an FDM(Frequency Division Multiplexing) method.

The SVC encoder (245100) performs SVC encoding on the broadcast data andoutputs the SVC-encoded data as the base layer data and the enhancementlayer data. The base layer data are equally transmitted from a 1^(st)transmission antenna (Tx1; 245300) and a 2^(nd) transmission antenna(Tx2; 245400). And, the enhancement layer data are processed with MIMOencoding by the MIMO encoder (245200), thereby being respectivelyoutputted through the 1^(st) transmission antenna (245300) and the2^(nd) transmission antenna (245400) as identical data or as differentdata.

At this point, in order to enhance data transmission efficiency, theMIMO transmitting system of FIG. 41 may process data by using the FDMmethod. Most particularly, by using the OFDM method, the MIMOtransmitting system may transmit data through multiple subcarriers. Asdescribed above, the transmitting system using the OFDM method mayallocate subcarriers as a subcarrier used for transmitting SISO/MISOsignals and as a subcarrier used for transmitting an MIMO signal,thereby being capable transmitting each signal. The base layer databeing outputted from the SVC encoder (245100) may be equally transmittedfrom multiple antennae through the SISO/MISO carrier, and theenhancement layer data being processed with MIMO encoding may betransmitted from multiple antennae through the MIMO carrier.

The receiving system receives an OFDM symbol. Then, the receiving systemperforms SISO/MISO decoding on the data corresponding to the SISO/MISOcarrier, so as to acquire the base layer data. And, the receiving systemperforms MIMO decoding on the data corresponding to the MIMO carrier, soas to acquire the enhancement layer data. Thereafter, based upon thechannel status and the receiving system, when the MIMO decoding processcannot be performed, the decoding process may be performed by using onlythe base layer data. Alternatively, when the MIMO decoding process canbe performed, the decoding process may be performed by using both thebase layer data and the enhancement layer data. Thus, a correspondingservice may be provided. In case of the second embodiment of the presentinvention, since the MIMO processing may be performed after mapping thebit information of the service to a symbol, the MIMO encoder (245200)may be positioned after the constellation mapper. Accordingly, thestructure of the receiving system may be more simplified as compared tothe structure of the receiving system shown in FIG. 40.

FIG. 42 illustrates a MIMO transmission system using an SVC and abroadcast signal transmitting method according to yet another embodimentof the present invention.

As shown in FIG. 42, the MIMO transmitting system may include an SVCencoder (246100), which encodes broadcasting data by using the SVCmethod, and a MIMO encoder (246200), which distributes data by using aspatial diversity or spatial multiplexing method, so that the data canbe transmitted to multiple antennae. FIG. 42 illustrates an exemplarytransmitting system using a layer PLP method or a TDM method.

In the embodiment shown in FIG. 42, the transmitting system mayrespectively transmit SVC-encoded base layer data and SVC-encodedenhancement layer data through an SISO/MISO slot and a MIMO slot. Thisslot may correspond to a time unit slot or a frequency unit slot of thetransmission signal. And, in the embodiment shown in FIG. 42, the slotis illustrated as a time unit slot. Furthermore, this slot may alsocorrespond to a PLP.

The receiving system may determine the slot type of the slot that isbeing received. And, the receiving system may receive base layer datafrom the SISO/MISO slot, and the receiving system may receiveenhancement layer data from the MIMO slot. And, as described above,based upon the channel and the receiving system, when the MIMO decodingprocess cannot be performed, the decoding process may be performed byusing only the base layer data. Alternatively, when the MIMO decodingprocess can be performed, the decoding process may be performed by usingboth the base layer data and the enhancement layer data. Thus, acorresponding service may be provided.

According to the embodiment of the present invention, the MIMO encoder(244200, 245200, 246200) of FIG. 40 to FIG. 42 may use at least one ofthe MIMO encoding methods proposed in the first embodiment to the thirdembodiment. This is merely exemplary, and, therefore, the MIMO encodingprocess may also be performed by using the SM method or the GC method.

In the present invention, the base layer data and the enhancement layerdata may be transmitted by using one PLP. And, each of the base layerdata and the enhancement layer data may be respectively transmitted byusing different PLPs.

According to an embodiment of the present invention, the base layer datamay be transmitted through a T2 frame (i.e., a terrestrial broadcastingframe), and the enhancement layer data may be transmitted through an FEFpart.

According to another embodiment of the present invention, the base layerdata and the enhancement layer data may only be transmitted through theFEF part.

In the description of the present invention, the FEF part, whichtransmits the base layer data and the enhancement layer data, will bereferred to as a MIMO broadcasting frame for simplicity. Herein, theMIMO broadcasting frame will be used in combination with a signal frameor a transmission frame.

Also, in the description of the present invention, the base layer dataand the enhancement layer data will be collectively referred to as MIMObroadcasting data for simplicity.

Hereinafter, in the following description of the present invention, theMIMO broadcasting data may be generated by any one of the 1^(st) methodto 3^(rd) method, which will be described as presented below, therebybeing transmitted. Alternatively, the MIMO broadcasting data may also begenerated and transmitted by a combination of at least one or more ofthe 1^(st) method to 3^(rd) method described below.

(1) Method for Transmitting MIMO Broadcasting Data to a Specific PLP

In the present invention, a method for including MIMO broadcasting datato a specific PLP and transmitting the specific PLP, afterdifferentiating the specific PLP from a PLP including the terrestrialbroadcasting (e.g., T2 broadcasting) data may be used. In this case, thespecific PLP may be used in order to transmit the MIMO broadcastingdata. And, at this point, additional information on the specific PLP maybe signaled, so as to prevent any malfunction in the conventionalreceiving system from occurring. Hereinafter, the specific PLP includingthe MIMO broadcasting data may be referred to as a MIMO broadcastingPLP, and the PLP including the terrestrial broadcasting data may bereferred to as a terrestrial broadcasting PLP.

Since the conventional terrestrial broadcasting signal receivingapparatus may not be capable of processing the MIMO broadcasting data,additional information for identifying the terrestrial broadcasting PLPand the MIMO broadcasting PLP is required to be signaled. At this point,the signaling of the information for identifying the PLP type may use areserved field included in the L1 signaling information. For example, inorder to identify the PLP type, a PLP_TYPE field of theL1-post-signaling information may be used. At this point, the MIMObroadcasting PLP may be indicated by using any one of the values rangingfrom 011˜111 as the PLP_TYPE field value.

When transmitting the PLP, in order to acquire a more enhancedrobustness, a new modulation method and a new coding rate of the errorcorrection code may be used. In this case, in order to identify suchmodulation method and coding rate of the error correction code, theL1-post-signaling information may be used. According to an embodiment ofthe present invention, the present invention may use a PLP_COD field ofthe L1-post-signaling information in order to indicate the coding rateof the MIMO broadcasting PLP. For example, in order to identify thecoding rate of the MIMO broadcasting PLP, any one of 110 or 111 may beused as the PLP_COD field value.

Furthermore, according to an embodiment of the present invention, thepresent invention may use a PLP_MOD field of the L1-post-signalinginformation in order to indicate a modulation method of the MIMObroadcasting PLP. For example, in order to identify the modulationmethod of the MIMO broadcasting PLP, any one of values 100 to 111 may beused as the PLP_MOD field value.

At this point, the base layer data and the enhancement layer dataconfiguring the MIMO broadcasting data may be collectively transmittedto a single PLP, or may be separately transmitted to each PLP. Forexample, when the base layer data are transmitted to the PLP of the baselayer, and when the enhancement layer data are transmitted to the PLP ofthe enhancement layer, the receiving apparatus may use a PLP_PROFILEfield, so as to indicate whether the current PLP corresponds to the baselayer PLP or to the enhancement layer PLP.

(2) Method for Transmitting MIMO Broadcasting Data to a Specific Frames

In the present invention, a method for including MIMO broadcasting datato a specific frame and transmitting the specific frame, afterdifferentiating the specific frame from a frame including theconventional terrestrial broadcasting data may be used. In this case,the specific frame may be used in order to transmit the MIMObroadcasting data. And, at this point, additional information on thespecific frame may be signaled, so as to prevent any malfunction in theconventional receiving system from occurring. Hereinafter, the specificframe including the MIMO broadcasting data may be referred to as a MIMObroadcasting frame, and the frame including the terrestrial broadcastingdata may be referred to as a terrestrial broadcasting frame.Additionally, in case the specific frame including the MIMO broadcastingframe corresponds to an FEF, the FEF may be referred to as an MIMObroadcasting frame.

The present invention may differentiate the terrestrial broadcastingdata from the MIMO broadcasting data in frame units and may transmit thedifferentiated data accordingly. And, at this point, by identifying aframe by using the L1 signaling information, and by ignoring (ordisregarding) the MIMO broadcasting frame, the convention terrestrialbroadcasting receiving apparatus may be prevented from malfunctioning.

(3) Method for Transmitting a MIMO Broadcasting PLP to a TerrestrialBroadcasting Frame and a MIMO Broadcasting Frame

The present invention may transmit a PLP including the MIMO broadcastingdata through a terrestrial broadcasting frame and a MIMO broadcastingframe. For example, the base layer data may be transmitted through theterrestrial broadcasting frame, and the enhancement layer data may betransmitted through the MIMO broadcasting frame. In this case, unlikethe above-described embodiments of the present invention, since a MIMObroadcasting PLP also exists in the terrestrial broadcasting frame, arelation between interconnected PLPs existing in the terrestrialbroadcasting frame and in the MIMO broadcasting frame, is required to besignaled. In order to do so, the L1 signaling information should also beincluded in the MIMO broadcasting frame, and the information on the MIMObroadcasting PLP, which exists within the frame, may be transmittedalong with the L1 signaling information of the terrestrial broadcastingframe.

Fields respective to the PLP being included in the L1-post-signalinginformation of each frame may be used for the connection between theMIMO broadcasting PLPs existing in different frames. For example, thereceiving system may use at least one of a PLP_ID field, a PLP_TYPEfield, a PLP_PAYLOAD_TYPE field, and a PLP_GROUP_ID field, which areincluded in the L1-post-signaling information, so as to verify theinterconnection relation of the MIMO broadcasting PLPs included indifferent frames. Then, desired MIMO broadcasting PLPs may beconsecutively decoded, so as to acquire a service.

The terrestrial broadcasting PLP existing in the conventionalterrestrial broadcasting frame (i.e., T2 frame) may be pre-defined bythe terrestrial broadcasting system, so as to be transmitted to asupported transmission mode. Also, as described above, the terrestrialbroadcasting PLP may be transmitted in a new transmission modesupporting the MIMO system. For example, as described above, a MIMObroadcasting PLP being included in the terrestrial broadcasting framemay be transmitted in a transmission mode of terrestrial broadcasting asa base layer by using the MISO or SISO method, and a MIMO broadcastingPLP being included in the MIMO broadcasting frame may be transmitted asan enhancement layer by using the MIMO method.

FIG. 43(a) illustrates an exemplary super frame structure according toanother embodiment of the present invention. Herein, FIG. 43(a) shows anexample of transmitting a base layer PLP through a terrestrialbroadcasting frame and transmitting an enhancement layer PLP through aMIMO broadcasting frame (i.e., FEF part). At this point, a PLP includingbase layer data may be transmitted by using an SISO method or a MISOmethod. And, a PLP including enhancement layer data may be transmittedby using an SISO method, a MISO method, or a MIMO method.

FIG. 43(b) illustrates an exemplary super frame structure according toyet another embodiment of the present invention. Herein, FIG. 43(b)shows an example of transmitting both a base layer PLP and anenhancement layer PLP through a MIMO broadcasting frame (i.e., FEFpart).

At this point, a base layer PLP including base layer data may betransmitted by using an SISO method or a MISO method. And, anenhancement layer PLP including enhancement layer data may betransmitted by using an SISO method, a MISO method, or a MIMO method. Asdescribed above, the ratio between the base layer PLP and theenhancement layer PLP within the MIMO broadcasting frame may vary withina range of 0˜100%.

FIG. 43(c) illustrates an exemplary super frame structure according toyet another embodiment of the present invention. Herein, FIG. 43(c)shows an example of transmitting both base layer data and enhancementlayer data through a MIMO broadcasting frame (i.e., FEF part). However,unlike in the example shown in FIG. 43(b), in the example shown in FIG.43(c), the base layer and the enhancement layer are transmitted by beingdifferentiated as carriers, instead of being differentiated as PLPs.More specifically, the data corresponding to the base layer and the datacorresponding to the enhancement layer may respectively be allocated toeach separate subcarrier, so as to be processed with OFDM modulation,thereby being transmitted.

FIG. 44 illustrates a broadcasting signal transmitting apparatusaccording to another embodiment of the present invention.

The broadcasting signal transmitting apparatus of FIG. 44 corresponds toan exemplary embodiment, which identifies the base layer data as thebase layer PLP, and which the enhancement layer data as the enhancementlayer PLP, thereby transmitting the identified (or differentiated) PLPs.Although it is not shown in FIG. 44, the broadcasting signaltransmitting apparatus includes an SVC encoder, which performs SVCencoding on data, so as to transmit the SVC encoded data as base layerdata and enhancement layer data. At this point, according to theembodiment of the present invention, it is described herein that thebase layer data are included in PLP1, and that the enhancement layerdata are included in PLP2.

The broadcasting signal transmitting apparatus of FIG. 44 includes afirst BICM module (258100) for performing BICM processing on a baselayer PLP (PLP1), a second BICM module (258200) for performing BICMprocessing on an enhancement layer PLP (PLP2), a frame builder (258300)receiving PLPs that are processed in the first and second BICM modules(258200), thereby building a frame, a MIMO encoder (258400) performingMIMO, MISO, or SISO processing on the output data of the frame builder(258300), a first OFDM generator (258500) performing OFDM modulation ona first transmission signal, which is outputted from the MIMO encoder(258400), and a second OFDM generator (258600) performing OFDMmodulation on a second transmission signal, which is outputted from theMIMO encoder (258400).

Reference may be made on the description of the operations of the blocksincluded in the above-described broadcasting signal transmittingapparatus having the same names as the first BICM module (258100), thesecond BICM module (258200), the frame builder (258300), the MIMOencoder (258400), the first OFDM generator (258500), and the second OFDMgenerator (258600), and, therefore, a detailed description of the samewill be omitted herein.

In the broadcasting signal transmitting apparatus of FIG. 44, the MIMOencoder (258400) may be positioned between a constellation mapper and atime interleaver within the second BICM module (258200).

FIG. 45 illustrates a broadcasting signal receiving apparatus accordingto yet another embodiment of the present invention.

When the base layer and the enhancement layer are identified andtransmitted as PLPs, as shown in FIG. 44, the broadcasting signalreceiving apparatus of FIG. 45 corresponds to an exemplary embodiment ofa broadcasting signal receiving apparatus receiving and processing suchPLPs. Although it is not shown in FIG. 45, the broadcasting signalreceiving apparatus includes an SVC decoder, which performs SVC decodingon base layer and enhancement data, so as to recover the data. At thispoint, according to the embodiment of the present invention, the baselayer data are included in PLP1, and the enhancement layer data areincluded in PLP2, thereby being received.

The broadcasting signal receiving apparatus of FIG. 45 includes OFDMdemodulators (259100, 259200) performing OFDM demodulation on signalsreceived through multiple antennae, an MIMO decoder (259300) performingMIMO decoding on the signals OFDM-demodulated from the OFDM demodulators(259100, 259200) in accordance with the channel characteristics, a framedemapper (259400) outputting base layer PLP and enhancement layer PLPfrom the signal frame including the MIMO-decoded signal, and BICMdecoder (259500, 259600) each performing an inverse process of the BICMmodule for each PLP and correcting errors occurring due to thetransmission channel.

For the detailed description on the operations of each of the OFDMdemodulators (259100, 259200), the MIMO decoder (259300), the framedemapper (259400), and the BICM decoders (259500, 259600) of thebroadcasting signal receiving apparatus shown in FIG. 45, reference maybe made to the description on the operations of the same blocks includedin the above-described broadcasting signal receiving apparatus. And,therefore, detailed description of the same will be omitted.

The broadcasting signal receiving apparatus of FIG. 45 may first acquirebase layer data from the PLP (PLP1), which is outputted from the firstBICM decoder (259500), and enhancement layer data from the PLP (PLP2),which is outputted from the second BICM decoder (259600), and may thenperform SVC decoding on the acquired data, so as to provide a respectiveservice. In case the broadcasting signal receiving apparatus acquiresonly the base layer data, the broadcasting signal receiving apparatusmay decode the base layer data, so as to provide a basic service. And,in case the broadcasting signal receiving apparatus acquires the baselayer data along with the enhancement layer data, the broadcastingsignal receiving apparatus may provide a service having higher picturequality/sound quality.

Meanwhile, according to the embodiment of the present invention, in caseboth the base layer data and the enhancement layer data are transmittedby using a single PLP, a mux may be further included in from of the BICMmodule of the broadcasting signal receiving apparatus shown in FIG. 44.

More specifically, the base layer data and the enhancement layer databeing outputted from the SVC encoder may be included in a single PLP(PLP1), so as to be inputted to the mux. In this case, the mux mayidentify the base layer data and the enhancement layer data, which areincluded in the PLP (PLP1), thereby outputting the identified data tothe respective BICM module (258100, 258200). In this case, thebroadcasting signal receiving apparatus may be equipped with a timeinterleaver, and the base layer and the enhancement layer may be coupled(or combined) by the time interleaver, thereby being processed withinterleaving while the two layers are intermixed with one another. Thus,diversity of the time domain may be gained. At this point, according tothe embodiment of the present invention, the data corresponding to thebase layer within the PLP may be SISO or MIMO-processed, and the datacorresponding to the enhancement layer may be MIMO-processed.

Additionally, in case both the base layer data and the enhancement layerdata are both transmitted from the transmitting end by using a singlePLP, the frame demapper of the broadcasting signal receiving apparatusshown in FIG. 45 extracts a PLP (PLP1), which includes the data of thebase layer and the data of the enhancement layer, and outputs theextracted PLP. In this case, the broadcasting signal receiving apparatusmay be equipped with a time deinterleaver, and the time deinterleavermay perform time deinterleaving on the PLP (PLP2), so as to divide thePLP into base layer data and enhancement layer data and to repositioneach data type within the time domain, thereby outputting therepositioned data type to each stream. Each of the BICM decoders(259500, 259600) processes a base layer stream and an enhancement layerstream.

At this point, the base layer data and the enhancement layer data, whichare error-corrected and outputted from the BICM decoders (259500,259600), may be SVC-decoded, so as to provide a service. In the casewhen only the base layer data are acquired, the base layer data may bedecoded, so as to provide the basic (or essential) service. And, whenboth the base layer data and the enhancement layer data are acquired, aservice having higher picture quality/sound quality may be provided.

In the broadcasting signal receiving apparatus of FIG. 45, the MIMOdecoder (259300) may also be located between the frame demapper (259400)and the HIGH decoders (259500, 259600).

Hereinafter, a signaling method of the signaling method according to thepresent invention will be described in detail. The signal frameaccording to the present invention may be divided into a preamble regionand a data region, and the preamble region may be configured of a P1symbol and one or more P2 symbols, and the data region may be configuredof multiple data symbols. At this point, the preamble region may furtherinclude an AP1 symbol after the P1 symbol. And, in this case, the P1symbol and the AP1 symbol may be consecutively transmitted.

Herein, the P1 symbol transmits P1 signaling information, the APT symboltransmits AP1 signaling information, and the one or more P2 symbol eachtransmits L1 signaling information and signaling information included inthe common PLP (i.e., L2 signaling information). The signalinginformation being included in the common PLP may be transmitted througha data symbol. Therefore, in light of a signal frame over a physicallayer, the preamble region may include a P1 signaling information regionto which the P1 signaling information is signaled, an L1 signalinginformation region to which the L1 signaling information is signaled,and an entire portion or a partial portion of a common PLP region towhich the L2 signaling information is signaled. Herein, the common PLPregion may also be referred to as an L2 signaling information region. Ifa signal frame includes an AP1 symbol, the preamble region includes theP1 signaling information region, the AP1 signaling information region,the L1 signaling information region, and an entire portion or a partialportion of the common PLP region.

The L1 signaling information includes L1-pre-signaling information andL1-post-signaling information. The L1-post-signaling information thenincludes Configurable L1-post-signaling information, DynamicL1-post-signaling information, Extension L1-post-signaling information,and CRC information, and may further include L1 padding data.

FIG. 46 illustrates an exemplary syntax structure of P1 signalinginformation according to an embodiment of the present invention.

According to the embodiment of the present invention, in FIG. 46, the P1signaling information is assigned with 7 bits and includes a 3-bit S1field and a 4-bit S2 field. In the S2 field, among the 4 bits, the first3 bits are described as S2 field1 and the 1 bit is described as S2field2.

The S1 field signals a preamble format. For example, when the 81 fieldvalue is equal to 000, this indicates that the preamble corresponds to aT2 preamble, and that data are transmitted in an SISO format (T2_SISO).When the S1 field value is equal to 001, this indicates that thepreamble corresponds to a T2 preamble, and that data are transmitted inan MISO format (T2_MISO). When the S1 field value is equal to 010, thisindicates that the preamble corresponds to a non-T2 preamble.

The S2 field signals FFT size information. According to the embodimentof the present invention, the FFT size may correspond to 1 k, 2 k, 4 k,8 k, 16 k, and the GI size may correspond to 1/128, 1/32, 1/16, 19/256,1/8, 19/128, 1/4. The FFT size signifies a number of subcarriersconfiguring a single OFDM symbol. When the S2 filed2 value is equal to0, this indicates that, in the current transmission, all preambles arebeing transmitted as the same type, and when the field value is equal to1, this indicates that the preambles are each transmitted as differenttypes.

FIG. 47 illustrates an exemplary syntax structure of AP1 signalinginformation according to an embodiment of the present invention.

According to the embodiment of the present invention, in FIG. 47, theAP1 signaling information is assigned with 7 bits and includes a 4-bitPILOT_PATTERN field and a 3-bit L1_PRE_SPREAD_LENGTH field.

The PILOT_PATTERN field indicates a pilot pattern of the correspondingsignal frame. In the present invention, by transmitting pilot patterninformation through the AP1 symbol, even when the P2 symbol is nottransmitted, and even when the L1 signaling information is spread todata symbols of the data region, the receiver may be aware of the pilotpattern prior to decoding the L1 signaling information of the dataregion.

The L1_PRE_SPREAD_LENGTH field indicates a length of a section withinthe data region in which the L1-pre-signaling information is spread.More specifically, among the data symbols of the signal frame, thisfield indicates a number of data symbols included in a section to whichthe L1-pre-signaling information is being spread. In the presentinvention, the section to which the L1-pre-signaling information isbeing spread will be referred to as an L1 pre spread section. If theL1_PRE_SPREAD_LENGTH field value is equal to ‘000’, this indicates thatthe L1 signaling information is not spread in the data region of thecorresponding signal frame.

In FIG. 47, since the fields included in the AP1 signaling informationand significance of the values of each field are merely examples givento facilitate the understanding of the present invention, and since thefields that can be included in the AP1 signaling information and thesignificance of the respective field values may be easily modified byanyone skilled in the art, the present invention will not be limitedonly to the examples given herein.

FIG. 48 illustrates an exemplary syntax structure of L1-pre-signalinginformation according to an embodiment of the present invention. TheL1-pre-signaling information includes information required for decodingthe L1-post-signaling information.

The fields being included in the L1-pre-signaling information of FIG. 48will hereinafter be described in detail.

A TYPE field may be assigned with 8 bits and may indicate the type of aninput stream being transmitted in a super frame. More specifically, theinput stream may correspond to TS, GS, TS+GS, IP, and so on, and suchidentification may use the TYPE field.

A BWT_EXT field is assigned with 1 bit and may indicate whether or not abandwidth extension of an OFDM symbol is to be performed.

An S1 field is assigned with 3 bits and performs the same role as the S1field included in the P1 signaling information of FIG. 46. An S2 fieldis assigned with 4 bits and performs the same role as the S2 fieldincluded in the P1 signaling information of FIG. 46. According to theembodiment of the present invention, an L1_REPETITION_FLAG field isassigned with 1 bit and may indicate whether or not L1-post-signalinginformation related to the current frame is signaled to the P2 symbol.If the L1 signaling information of the next signal frame is configuredto have a structure to which the data symbols of the current signalframe are spread, the L1_REPETITION_FLAG field may also be used in orderto indicate whether or not the L1 signaling information of the nextsignal frame has been spread to the current signal frame. For example,when the L1_REPETITION_FLAG field is equal to 1, this indicates that theL1 signaling information has been spread to the current signal frame,and when the corresponding field is equal to 0, this indicates that the141 signaling information has not been spread to the current signalframe.

A GUARD_INTERVAL field is assigned with 3 bits and indicates a GI sizeof the current transmission frame. The CI size indicates an occupationratio of the GI within a single OFDM symbol. Accordingly, the OFDMsymbol length may vary depending upon the FFT size and the GI size.

A PAPR field is assigned with 4 bits and indicates a PAPR reductionmethod. The PAPR method used in the present invention may correspond toan ACE method or a TR method.

An L1_MOD field is assigned with 4 bits and may indicate a QAMmodulation type of the L1-post-signaling information.

An L1_COD field is assigned with 2 bits and may indicate a code rate ofthe L1-post-signaling information.

An L1_FEC_TYPE field is assigned with 2 bits and may indicate an FECtype of the L1-post-signaling information.

An L1_POST_SIZE field is assigned with 18 bits and may indicate the sizeof the coded and modulated L1-post-signaling information.

An L1_POST_INFO_SIZE field is assigned with 18 bits and may indicate thesize of the L1-post-signaling information in bit units.

A PILOT_PATTERN field is assigned with 4 bits and may indicate adistributed pilot pattern that is inserted in the current signal frame.

A TX_ID_AVAILABILITY field is assigned with 8 bits and may indicate atransmitting apparatus identification capability within the currentgeographical cell range.

A CELL_ID field is assigned with 16 bits and may indicate an identifieridentifying a geographical cell within a network for mobile broadcasting(NGH).

A NETWORK_ID field is assigned with 16 bits and may indicate anidentifier identifying the current network.

A SYSTEM_ID field is assigned with 16 bits and may indicate anidentifier identifying the system.

A NUM_NGH_FRAMES field is assigned with 8 bits and may indicate a numberof NGH frame within the current super frame.

A NUM_T2_FRAMES field is assigned with 8 bits and may indicate a numberof T2 frame within the current super frame. This field is useful fordetermining the super frame structure and may be used for calculatingthe information for directly hopping to the next NGH frame.

A L1_POST_SPREAD_LENGTH field is assigned with 12 bits and may indicatethe length of a section within the data region to which theL1-post-signaling information is being spread. More specifically, amongthe data symbols of the signal frame, this field may indicate the numberof data symbols being included in the section to which theL1-post-signaling information is being spread. In the present invention,the section to which the L1-post-signaling information is being spreadwill be referred to as an L1 post spread section. If all of theL1_POST_SPREAD_LENGTH field value is equal to 0, this signifies that theL1-post-signaling information is not spread to the data region of thecorresponding signal frame.

A NUM_DATA_SYMBOLS field is assigned with 12 bits and may indicate anumber of data symbols included in the current signal frame, with theexception for the P1, AP1, P2 symbols.

A NUM_MISO_SYMBOLS field is assigned with 12 bits and may indicate anumber of MISO symbols among the diverse data symbols.

A MIMO_SYMBOL_INTERVAL field is assigned with 12 bits and may indicate anumber of MISO symbols between two MIMO symbol parts.

A MIMO_SYMBOL_LENGTH field is assigned with 12 bits and may indicate anumber of MIMO symbols in one MIMO symbol part.

A REGEN_FLAG field is assigned with 3 bits and may indicate and mayindicate a number of signal regeneration performed by the repeater.

An L1_POST_EXTENSION field is assigned with 1 bit and may indicatewhether or not an extension field exits in the L1-post-signalinginformation.

A NUM_RF field is assigned with 3 bits and may indicate a number of RFswithin the current system.

A CURRENT_RF_IDX field is assigned with 3 bits and may indicate an indexof the current RF channel.

A RESERVED field is assigned with 10 bits and corresponds to a fieldthat is reserved for future usage.

A CRC-32 field is assigned with 32 bits and may indicate a CRC errorextraction code of the 32 bits.

In FIG. 48, since the fields included in the L1-pre-signalinginformation and significance of the values of each field are merelyexamples given to facilitate the understanding of the present invention,and since the fields that can be included in the L1-pre-signalinginformation and the significance of the respective field values may beeasily modified by anyone skilled in the art, the present invention willnot be limited only to the examples given herein.

FIG. 49 illustrates an exemplary syntax structure of configurableL1-post-signaling information according to an embodiment of the presentinvention. The configurable L1-post-signaling information may includeparameters required by the receiver for decoding a PLP and, moreparticularly, configurable L1-post-signaling information may includediverse information that can be equally applied during a signal frame.

The fields being included in the configurable L1-post-signalinginformation of FIG. 49 will hereinafter be described in detail.

A SUB_SLICES_PER_FRAME field is assigned with 15 bits and may indicate anumber of sub-slices included in a signal frame.

A NUM_PLP field is assigned with 8 bits and may indicate a number ofPLPs within the current super frame.

A NUM_AUX field is assigned with 4 bits and may indicate a number ofauxiliary streams.

An AUX_CONFIG_RFU field is assigned with 8 bits and corresponds to aregion reserved for a future usage.

Subsequently, a for loop (hereinafter referred to as a frequency loop),which is repeated as many times as the number of RFs within the currentsystem, is signaled. The NUM_RF field is signaled to theL1-pre-signaling information.

Hereinafter, fields being included in the frequency loop will bedescribed in detail.

An RF_IDX field is assigned with 3 bits and may indicate an index ofeach frequency within an RF channel.

A FREQUENCY field is assigned with 32 bits and may indicate a centerfrequency of the RF channel.

An FEF_TYPE field, an FEF_LENGTH field, and an FEF_INTERVAL field, whichare shown below, correspond to fields that are used only when the LSB ofthe S2 field is equal to 1, i.e., when the S2 field is expressed asS2=‘xxx1’.

The FEF_TYPE field is assigned with 4 bits and may indicate an FEF(Future extension frame) type.

The FEF_LENGTH field is assigned with 22 bits and may indicate a numberof elementary periods of a related FEF part.

The FEF_INTERVAL field is assigned with 8 bits and may indicate a numberof T2 frames existing between two FRF parts.

A NEXT_NGH_SUPERFRAME field is assigned with 8 bits and may indicate anumber of super frames existing between the current super frame and thenext super frame, which includes the next NGH frame.

A RESERVED_2 field is assigned with 32 bits and corresponds to a fieldthat is reserved for a future usage.

Subsequently, a for loop (hereinafter referred to as an auxiliary streamloop), which is repeated as many times as the number of auxiliarystreams (NUM_AUX field value−1), is signaled, a 32-bit AUX_RFU field,which is reserved for a future usage, is included herein.

Subsequently, a for loop (hereinafter referred to as a PLP loop), whichis repeated as many times as the number of PLPs within the current superframe (NUM_PLP field value−1), is signaled.

Hereinafter, fields being included in the PLP loop will be described indetail.

A PLP_ID field is assigned with 8 bits and may indicate an identifieridentifying the corresponding PLP.

A PLP_TYPE field is assigned with 3 bits and may indicate whether thecorresponding PLP corresponds to a common PLP, a Type1 data PLP, or aType2 data PLP. Additionally, the PLP_TYPE field may indicate whetherthe corresponding PLP corresponds to a PLP being included in a pluralityof PLP groups, or to a group PLP being included in a single PLP group.

A PLP_PAYLOAD_TYPE field is assigned with 5 bits and may indicate thetype of a PLP payload. More specifically, the data included in thepayload of the PLP may correspond to GFPS, GCS, GSE, TS, IP, and so on,and such identification may use the PLP_PAYLOAD_TYPE field.

The PLP_PROFILE field is assigned with 2 bits and may indicate a profileof the corresponding PLP. More specifically, this field indicateswhether the corresponding field is a mandatory (or required) PLP or anoptional (or selective) PLP. For example, when the PLP of the video datais identified as a PLP for transmitting a base layer and a PLP fortransmitting an enhancement layer, the PLP transmitting the base layerbecomes the mandatory PLP, and the PLP transmitting the enhancementlayer becomes the optional PLP. Additionally, the common PLP correspondsto a mandatory PLP. More specifically, depending upon the receivercharacteristic, such as a mobile receiver, a fixed-type receiver, and soon, the receiver may use the PLP_PROFILE field so as to verify by whichreceiver the component of the broadcast service being transmitted to thecurrent PLP may be used, and depending upon the receiver characteristic,the receiver may determine whether or not to receive the current PLP.

An FF_FLAG field is assigned with 1 bit and, when 2 or more RF channelsare being used, this field may indicate a fixed frequency mode.

A FIRST_RF_IDX field is assigned with 3 bits and may indicate an RFindex of a first signal frame of the corresponding PLP.

A FIRST_FRAME_IDX field is assigned with 8 bits and may indicate a frameindex of the first signal frame of the corresponding PLP.

A PLP_GROUP_ID field is assigned with 8 bits and may indicate anidentifier identifying a PLP group related to the corresponding PLP.

A PLP_MOD field is assigned with 3 bits and may indicate the code rateof the corresponding PLP. In the present invention, any one of the coderates of 1/4, 1/3, 2/5, 1/2, 3/5, 2/3, 3/4, 4/5, 5/6 may be used in thecorresponding PLP.

A PLP_MOD field is assigned with 3 bits and may indicate a constellationsize (i.e., modulation format) of the corresponding PLP. In the presentinvention, any one of the modulation formats (or modulations types) ofBPSK, QPSK, 16QAM, 64QAM, 256QAM may be used.

A PLP_MIMO_TYPE field is assigned with 2 bits and may indicate whetherthe corresponding PLP corresponds to a MIMO type or a MISO type.

For example, a PLP_MOD field value, i.e., the constellation size may bedecided by a combination with the PLP_MIMO_TYPE field. If thePLP_MIMO_TYPE field value indicates the MISO, the PLP_MOD field may beused for symbol re-mapping. If the PLP_MIMO_TYPE field value indicatesthe MIMO, after performing MIMO processing, the PLP_MOD field may beinterpreted as a constellation size having a spectrum effect, as aresult of the MIMO processing.

A PLP_ROTATION field is assigned with 1 bit and may indicate whether ornot constellation rotation and re-mapping of the PLP has been used.

A PLP_FEC_TYPE field is assigned with 2 bits and may indicate an FECtype of the corresponding PLP.

A PLP_NUM_BLOCKS_MAX field is assigned with 10 bits and may indicate amaximum number of PLPs included in the FEC blocks.

A FRAME_INTERVAL field is assigned with 8 bits and may indicate a T2frame interval within a super frame, when inter-frame interleaving isapplied.

A TIME_IL_LENGTH field is assigned with 8 bits and may indicate a timeinterleaver length (or depth).

A TIME_IL_TYPE field is assigned with 1 bit and may indicate the timeinterleaver type.

An IN_BAND_FLAG field is assigned with 1 bit and may indicate whether ornot in-band signaling exists.

A RESERVED_1 field is assigned with 16 bits and corresponds to a fieldthat is reserved in the PLP loop for a future usage.

The PLP loop may further include a PLP_COMPONENT_TYPE field. ThePLP_COMPONENT_TYPE field is assigned with 8 bits and may indicate thetype of data (or service component) being transmitted through thecorresponding PLP. Therefore, based upon the PLP_COMPONENT_TYPE field,the receiver may be capable of determining whether the type of thecomponent being transmitted through the corresponding PLP corresponds tobase layer video component, an enhancement layer video component, anaudio component, or a data component.

According to an embodiment of the present invention, the PLP group mayalso be referred to as an LLP (Link-Layer-Pipe), and the PLP_GROUP_IDfield may also be referred to as an LLP_ID field. Most particularly, anNIT, which is to be described later on, includes a PLP_GROUP_ID field,which is identical to the PLP_GROUP_ID field included in the L1signaling information. And, the NIT may also include atransport_stream_id field for identifying a transmission stream relatedto the PLP group. Therefore, by using the NIT, the receiver may becapable of knowing to which PLP group a specific stream is related. Morespecifically, in order to simultaneously decode streams (e.g., TSs)being transmitted through PLPs having the same PLP_GROUP_ID, the streamsthat are indicated by the transport_stream_id field of the NIT may bemerged, thereby being capable of recovering a single service stream.

Therefore, when the broadcasting signal is being transmitted in a TSformat, the receiver may merge the PLPs having the same PLP_GROUP_IDfield, so as to recover the initial (or original) TS.

If the broadcasting signal is transmitted in an IP format, the receivermay use the PLP_GROUP_ID field, so as to locate and find the servicecomponents related to a single service. And, by merging such servicecomponents, a single service may be recovered. Accordingly, the receivershould be capable of simultaneously receiving PLPs having the samePLP_GROUP_ID.

In FIG. 49, since the fields included in the configurableL1-post-signaling information and significance of the values of eachfield are merely examples given to facilitate the understanding of thepresent invention, and since the fields that can be included in theconfigurable L1-post-signaling information and the significance of therespective field values may be easily modified by anyone skilled in theart, the present invention will not be limited only to the examplesgiven herein.

FIG. 50 illustrates an exemplary syntax structure of dynamicL1-post-signaling information according to an embodiment of the presentinvention. The dynamic L1-post-signaling information may includeparameters required by the receiver for decoding a PLP and, moreparticularly, the dynamic L1-post-signaling information may includecharacteristic information corresponding to a signal frame that iscurrently being transmitted. Additionally, the dynamic L1-post-signalinginformation may also be signaled to an in-band, so that that thereceiver can efficiently process slicing.

The fields being included in the dynamic L1-post-signaling informationof FIG. 50 will hereinafter be described in detail.

A FRAME_IDX field is assigned with 8 bits and may indicate an index of acurrent signal frame within the super frame. For example, an index ofthe first signal frame within the super frame may be set to 0.

A SUB_SLICE_INTERVAL field is assigned with bits and may indicate anumber of OFDM cell existing between two sub-slices within the same PLP.

A TYPE_2_START field is assigned with 22 bits and may indicate astarting position among the OFDM cells of the Type2 data PLPs.

An L1_CHANGE_COUNTER field is assigned with 8 bits and may indicate anumber of super frame that remain before the L1 configuration (e.g.,contents of the fields included in the L1 pre signaling or content of aconfigurable part in the L1 post signaling).

A START_RF_IDX field is assigned with 3 bits and may indicate a start REindex of a next signal frame.

A RESERVED_1 field is assigned with 8 bits and corresponds to a fieldthat is reserved for a future usage.

A NEXT_NGH_FRAME field is assigned with 8 bits and corresponds to afield that is used only when the LSB of the S2 field is equal to 1,i.e., when the S2 field is expressed as S2=‘xxx1’. A NEXT_NGH_SUPERFRAMEfield indicates a number of T2 or FEF frames existing between the first12 frame within the next super frame, which includes an NGH frame, andthe next NGH frame. The NEXT_NGH_FRAME field and the NEXT_NGH_SUPERFRAMEfield may be used by the receiver for calculating a hopping amount forhopping to the next NGH frame. More specifically, the NEXT_NGH_FRAMEfield and the NEXT_NGH_SUPERFRAME field provide an efficient hoppingmechanism, when a large number of T2 frames are mixed with the FEF, andwhen not all of the FEFs are used only for the NGH frames. Mostparticularly, the receiver may perform hopping to the next NGH framewithout having to detect the P1 signaling information of all signalframes existing in the super frame and to decode the detected P1signaling information.

Subsequently, a for loop (hereinafter referred to as a PLP loop), whichis repeated as many times as the number of PLPs existing within thecurrent super frame (NUM_PLP field value−1), is signaled.

A PLP_ID field, a PLP_START field, and a PLP_NUM_BLOCKS field areincluded in the PLP loop. And, the corresponding field will hereinafterbe described in detail.

The PLP_ID field is assigned with 8 bits and may indicate an identifieridentifying a PLP.

The PLP_START field is assigned with 22 bits and may indicate a startingposition of OFDM cells of the current PLP.

The PLP_NUM_BLOCKS field is assigned with 10 bits and may indicate anumber of FEC blocks related to the current PLP.

A RESERVED_2 field is assigned with 8 bits and corresponds to a fieldincluded in the PLP loop that is reserved for a future usage.

A RESERVED_3 field is assigned with 8 bits and corresponds to a fieldthat is reserved for a future usage.

Field included in an auxiliary stream loop will hereinafter bedescribed.

Subsequently, a for loop (hereinafter referred to as an auxiliary streamloop), which is repeated as many times as the number of auxiliarystreams (NUM_AUX field value−1), is signaled, and a 48-bit AUX_RFU fieldis included herein for a future usage.

In FIG. 50, since the fields included in the dynamic L1-post-signalinginformation and significance of the values of each field are merelyexamples given to facilitate the understanding of the present invention,and since the fields that can be included in the dynamicL1-post-signaling information and the significance of the respectivefield values may be easily modified by anyone skilled in the art, thepresent invention will not be limited only to the examples given herein.

Meanwhile, the present invention may signal a PLP or a correlationbetween a PLP and service components, by using at least one of thePLP_GROUP_ID field, the PLP_TYPE field, the PLP_PROFILE field, and thePLP_COMPONENT_TYPE field of the PLP loop within the configurableL1-post-signaling information. Additionally, the present invention mayalso know the operation characteristics, such as the mobile performanceand data communication characteristics, of the PLP by using the PLP_CODfield and the PLP_MOD field.

Hereinafter, a signaling method for signaling a PLP or a correlationbetween a PLP and service components, by using the PLP_ID field, thePLP_GROUP_ID field, the PLP_COMPONENT_TYPE field, and the PLP_PROFILEfield, will be described in detail.

Hereinafter, the present invention provides a signaling method accordingto 4 different exemplary embodiments of the present invention. The 4different exemplary embodiments may be divided into cases when thebroadcast signal is being transmitted in a TS format and cases when thebroadcast signal is being transmitted in an IP format. In thedescription of the present invention, the first exemplary embodiment tothe third exemplary embodiment correspond to a signaling method whereinthe broadcast signal is transmitted in the TS format, and the fourthexemplary embodiment corresponding to a signaling method wherein thebroadcast signal is transmitted in the IP format.

Each exemplary embodiment of the present invention will be described indetail as presented below.

The first embodiment of the present invention corresponds to a signalingmethod enabling the receiver to merge PLPs included in the same PLPgroup by using the correlation between the PLP group, which is includedin the L1 signaling information region, and a service, thereby enablingthe receiver to recover a transport stream.

Just as in the first embodiment of the present invention, in addition toenabling the receiver to merge PLPs included in the same PLP group byusing the correlation between the PLP group, which is included in the L1signaling information region, and a service, thereby enabling thereceiver to recover a transport stream, the second embodiment of thepresent invention corresponds to a signaling method also enabling thereceiver to selectively receive desired PLPs in accordance with thereceiver characteristic, by using the correlation between a component,which configures the service included in the PLP, and a service.

The third embodiment of the present invention is similar to the secondembodiment of the present invention. However, the third embodiment ofthe present invention corresponds to a signaling method enablinginformation associated with the component, which configures the sameservice, to be transmitted through a base PLP, and enabling the receiverto selectively receive a PLP, which configures the service desired bythe receiver, in the physical layer.

The fourth embodiment of the present invention corresponds to asignaling method respective to a case when the broadcast signal is beingtransmitted in an IP format. In the signaling method according to thefourth embodiment of the present invention, the receiver may merge thecomponent being transmitted by the PLPs included in the same PLP group,by using a correlation between a service and a PLP, which transmits thecomponents being included in the service, and then the receiver mayrecover a service.

The signaling of L1 signaling information, L2 signaling information,PAT/PMT, and so on, respective to the correlation between the PLPs, theTSs (or IP streams), the service, and the components according to firstto fourth embodiments of the present invention may be performed by theinput pre-processor or input processor of the broadcasting signaltransmitting apparatus (or transmitter), or may be performed by the BICMmodule.

According to an embodiment of the present invention, when the inputstream corresponds to a TS stream, the input pre-processor of FIG. 9 mayperform signaling of the L1 signaling information and L2 signalinginformation and may generate PLPs including PAT/PMT and component PLPsconfiguring a service. Herein, the L2 signaling information may includeNIT, SDT, and so on.

According to another embodiment of the present invention, when the inputstream corresponds to a TS stream, the input pre-processor shown in FIG.13 may perform signaling of the L1 signaling information and L2signaling information, and may generate PLPS including ESG, providerinformation, bootstrap information, and so on, and component PLPsconfiguring a service. Herein, the L2 signaling information may an IPinformation table.

According to yet another embodiment of the present invention, signalingof the L1 signaling information, shown in FIG. 48 to FIG. 50, may beperformed by an L1 signaling generator included in the input processoror an L1 signaling generator included in the BICM module.

At this point, PLPs generated from the input pre-processor may beencoded by using the MISO method and then transmitted, or may be encodedby using the MIMO method and then transmitted. In the present invention,the PLP data being transmitted by using the MISO method may be referredto as MISO PLP data, and the PLP data being transmitted by using theMIMO method may be referred to as MIMO PLP data.

According to an embodiment of the present invention, if the BICM module,the frame builder, and the OFDM generator are identical to those shownin FIG. 19 to FIG. 21, the MIMO PLP data are processed with MIMOencoding by the MIMO encoder of the BICM module shown in FIG. 19, andthe MISO PLP data are processed with MISO encoding by the MISO encoderof the OFDM generator shown in FIG. 21. Additionally, the L1 signalinginformation may also be processed with MISO encoding by the MISO encoderincluded in the OFDM generator shown in FIG. 21.

According to another embodiment of the present invention, if the BICMmodule, the frame builder, and the OFDM generator are identical to thoseshown in FIG. 22 to FIG. 24, the MISO PLP data and the MIMO PLP data arerespectively processed with MISO encoding and MIMO encoding by the MISOencoder and the MIMO encoder, which are included in the BICM moduleshown in FIG. 22. Additionally, the L1 signaling information may also beprocessed with MISO encoding by the MISO encoder included in the BICMmodule shown in FIG. 22.

Meanwhile, according to an embodiment of the present invention, in thebroadcasting signal receiving apparatus (also referred to as areceiver), any one of the frame demapper, the BICM decoder, and theoutput processor may perform decoding on a PLP, a TS (or an IP stream),a service, L1/L2 signaling information to which the correlation betweenthe components is signaled, PAT/PMT or ESG, provider information,bootstrap information, and so on.

According to an embodiment of the present invention, if the OFDMdemodulator, the frame demapper, and the BICM decoder are identical tothose shown in FIG. 27, FIG. 30, and FIG. 31, the MISO encoded andreceived MISO PLP data are processed with MISO decoding by the MISOdecoder of the OFDM demodulator shown in FIG. 27, and the MIMO encodedand received MIMO PLP data are processed with MIMO decoding by the MIMOdecoder of the BICM decoder shown in FIG. 31. Additionally, the L1signaling information may also be processed with MISO decoding by theMISO decoder included in the OFDM demodulator shown in FIG. 27.

According to another embodiment of the present invention, if the OFDMdemodulator, the frame demapper, and the BICM decoder are identical tothose shown in FIG. 32 to FIG. 34, the MISO encoded and received MISOPLP data and the MIMO encoded and received MIMO PLP data arerespectively processed with MISO decoding and MIMO decoding by the MISOdecoder and the MIMO decoder, which are included in the BICM decodershown in FIG. 34. Additionally, the L1 signaling information may also beprocessed with MISO decoding by the MISO decoder included in the BICMdecoder shown in FIG. 34.

And, the process of selecting any one of the MISO PLP data and the MIMOPLP data and performing decoding on the selected PLP data may varydepending upon the first to fourth embodiments of the present invention.More specifically, according to any one of the first to fourthembodiments of the present invention, the present invention may becapable of knowing the PLPs in which the components configuring aservice are included. As a result, the PLPs configuring a specificservice may be selected and outputted from the frame demapper of FIG. 30or FIG. 33, and the selected and outputted PLPs may be processed witherror correction decoding by the BICM Decoder of FIG. 31 or FIG. 34,thereby being merged as a single service by the output processor of FIG.36.

According to another embodiment of the present invention, when the inputstream corresponds to a TS format, the broadcasting signal receivingapparatus of FIG. 37 may perform the above-described process. Morespecifically, any one of the frame demapper (210200), the PLPdeinterleaving and demodulator module (210500), the L1 decoder (210300),the BBF decoder and null packet reconstruction module (210600) mayperform decoding on the PLPs including L1/L2 signaling informationhaving the correlation between the PLP, TS, service, and componentssignaled thereto, and on PLPs including components. Most particularly,according to the embodiment of the present invention, in the presentinvention, the L1 decoder (210300) decodes the PLP including L1/L2signaling information having the correlation between the PLP, TS,service, and components signaled thereto and also including PAT/PMT,and, based upon the decoding result of the L1 decoder (210300), the PLPselecting module (210400) control the frame demapper (210200) so thatonly the PLPs of the components configuring the specific service can beoutputted from the frame demapper (210200). The PLPs that are selectedand outputted from the frame demapper (210200) pass through therespective PLP deinterleaving and demodulator module and the respectiveBBF decoder and null packet reconstruction module, so as to be merged toa single service in the TS merger. In the present invention, the PLPtransmitting the PSI/SI and, more particularly, the PAT/PMT will bereferred to as a base PLP.

According to yet another embodiment of the present invention, when theinput stream corresponds to an IP stream format, the broadcasting signalreceiving apparatus of FIG. 38 may perform the above-described process.More specifically, any one of the frame demapper (220200), the PUPdeinterleaving and demodulator module (220500), the L1 decoder (220300),and the BBF decoder (220600) may perform decoding on the PLPS includingL1/L2 signaling information having the correlation between the PLP, IPstream, service, and components signaled thereto, ESG, bootstrapinformation, provider information, and so on, and on PLPS includingcomponents. Most particularly, according to the embodiment of thepresent invention, in the present invention, the L1 decoder (210300)decodes the PLP including L1/L2 signaling information having thecorrelation between the PLP, IP stream, service, and components signaledthereto and also including ESG, bootstrap information, providerinformation, and so on, and, based upon the decoding result of the L1decoder (220300), the PLP selecting module (220400) control the framedemapper (220200) so that only the PLPs of the components configuringthe specific service can be outputted from the frame demapper (220200).The PLPs that are selected and outputted from the frame demapper(220200) pass through the respective PLP deinterleaving and demodulatormodule and the respective BBF decoder, thereby being outputted to therespective buffer. The description presented above may be applied to atleast one of the first to fourth embodiments of the present invention,which are presented below.

Hereinafter, each embodiment will be described in more detail.

First Embodiment (FIG. 51 to FIG. 53)

FIG. 51 illustrates a conceptual diagram of a correlation between aservice according to the first embodiment of the present invention and aPLP group.

In case of transmitting a broadcast signal of a TS format, the firstembodiment of the present invention corresponds to a signaling methodfor recovering a transport stream of a single service by acquiring aservice ID from the receiver, by using a PLP group ID associated to theacquired service ID, and by merging multiple PLPs being included in thesame PLP group.

As shown in FIG. 51, the L1 signaling information region (505100)according to the first embodiment of the present invention may includeinformation related to each of the multiple PLPs, i.e., a PLP_GROUP IDfield, a PLP_ID field, and so on, as shown in FIG. 48 to FIG. 50. Also,the L2 signaling information region (505200) may include an NIT and anSDT.

The NIT may include a PLP_GROUP_ID field, which is identical to thePLP_GROUP_ID field included in the L1 signaling information region(505100), and a transport_stream_id field. By using these fields, thereceiver may be capable of knowing to which PLP group a specifictransport stream is correlated. Also, the SDT may include atransport_stream_id field, which is identical to the transport_stream_idincluded in the NIT, and a service_id field. By using these fields, thereceiver may be capable of differentiating (or identifying) each of theservices being transmitted through a specific transport stream.

Eventually, among the many services included in a specific transportstream, the receiver may identify the desired service by using theservice_id field, which is included in the SDT. And, by using thetransport_stream_id field and the PLP_GROUP_ID field, which are includedin the NIT, the receiver may identify a PLP group, which is related withthe specific transport stream. Thereafter, the receiver may receive aPLP having the same PLP_GROUP_ID field, which is included in the L1signaling information region (505100). More specifically, the receivermay merge multiple PLPs, which are included in a PLP group beingcorrelated with the desired service, so as to recover a transportstream.

In other words, the receiver acquires an identifier of a service, whichis selected by the user, from the service_id field of the SDT. And, bymapping the transport_stream_id field of the SDT and thetransport_stream_id field of the NIT, a group identifier of the PLPstransmitting the components of the selected service may be acquired fromthe PLP_GROUP_ID field of the NIT. Subsequently, by mapping thePLP_GROUP_ID field of the NIT and the PLP_GROUP_ID field of the L1signaling information, each PLP identifier included in the PLP group maybe acquired from the PLP_ID field of the corresponding PLP. Thereafter,when the PLPS of the acquired PLP identifiers are merged, a TSconfiguring a service may be recovered.

Hereinafter, the fields, the NIT, and the SDT being included in the L1signaling information region (505100) according to the first embodimentof the present invention will be described in detail.

Since the L1 signaling information region (505100) according to thefirst embodiment of the present invention includes the same fields,which are described with reference to FIG. 48 to FIG. 50, the detaileddescription of the same will be omitted for simplicity.

The NIT corresponds to a table transmitting information related to thephysical structure of a multiplexer/transport stream being transmittedthrough the network, and diverse information respective to thecharacteristics of the network itself. The receiver may gain informationon the transport stream from the NIT.

The NIT according to the first embodiment of the present invention mayinclude a network_id field, a transport_stream_id field, and adelivery_system_descriptor loop.

Hereinafter, each field included in the NIT shown in FIG. 51 will bedescribed in detail.

The network_id field is used for identifying a network through which thecurrent broadcast signal is being transmitted.

The transport_stream_id field is used for identifying a transport streamthat is currently being transmitted.

The delivery_system_descriptor may include fields required or necessary)for matching the transport stream with the PLP and the transmittingsystem. Most particularly, the delivery_system_descriptor according tothe present invention may include a PLP_GROUP_ID field that is identicalto the PLP_GROUP_ID field included in the L1 signaling information.

Furthermore, the delivery_system_descriptor may include a system_idfield, system_parameter( ) field and a cell_parameter ( ) field.

A system_id field is used for identifying a system that is unique to thebroadcast network performing transmission.

A system_parameters( ) field may include parameters indicating thetransmitting system characteristics, such as whether the communicationis performed in a SISO/MIMO mode, a bandwidth, a guard interval, atransmission mode, and so on.

A cell_parameters( ) field may include parameters indicating cellinformation, such as a center frequency, a cell identifier, and so on.

The SDT corresponds to a table including information on multipleservices, which are included in a single transport stream. The SDTaccording to the first embodiment of the present invention may include atransport_stream_id field, and a service loop. And, the service loop mayinclude a service_id field and is repeated as many times as the numberof services included in a transmission frame.

Hereinafter, each field included in the SDT shown in FIG. 51 will bedescribed in detail.

Since the transport_stream_id field is identical to thetransport_stream_id field, which is included in the NIT, a detaileddescription of the same will be omitted for simplicity. The service_idfield is used for identifying multiple services included in thetransmission frame.

FIG. 52 shows a delivery_system_descriptor field of the NIT of FIG. 51according to the first embodiment of the present invention. Herein, thedelivery_system_descriptor field is used for connecting the PLP_GROUP_IDfield of the L1 signaling information region 500100 to the transportstream.

As shown in FIG. 52, the delivery_system_descriptor may include adescriptor_tag field, a descriptor_length field, a system_id field, aPLP_GROUP_ID field, and a first loop.

The first loop is used when the descriptor_length field has a sizelarger than 3. And, in this case, the first loop may include asystem_parameters( ) field and a second loop.

The second loop may include a cell_parameters( ) field.

Hereinafter, each field will be described in detail.

The descriptor_tag field is used for identifying each descriptor.

The descriptor_length field is used for indicating a total length of thedata portion of each descriptor.

The system_id field is used for identifying a system that is unique tothe broadcast network performing transmission.

The PLP_GROUP_ID field may identify a PLP group that is to be matchedand merged with the transport_stream_id field. Since the essentialdetails of the PLP_GROUP_ID field are identical to those of thePLP_GROUP_ID field shown in FIG. 36, a detailed description of the samewill be omitted for simplicity.

Since the system_parameters( ) field included in the first loop and thecell_parameters( ) field included in the second loop are identical tothose described in FIG. 51, a detailed description of the same will beomitted for simplicity.

FIG. 53 illustrates a flow chart showing the process steps of a servicescanning method of the receiver according to the first embodiment of thepresent invention.

The receiver receives a TP type broadcast signal transmitted in aspecific channel through tuning (S507100). In this case, in order toreceive a service desired by the user, the receiver requires informationon the service included in the transmission frame, which is beingtransmitted through the respective channel. Although this process stepis not shown in the drawing, this process step may be performed by thetuner of the receiver and may be modified or varied in accordance withthe intentions of the system designer.

Then, the receiver may decode the L1 signaling information included inthe transmission frame, so as to acquire a PLP ID, a PLP Group ID, and asystem ID, which are included in the transmission frame (S507200).Thereafter, the receiver may identify the PLP groups by using thedecoded PLP Group ID, so as to select the desired PLP group, and maydecode the PLP including the L2 signaling information and the PSI/SI(S507300). The receiver may decode the NIT and the SDT included in thedecoded L1 signal information, and the receiver may also decode aPAT/PMT included in the PLP, thereby being capable of storing serviceinformation associated with the transmitting system and the PLPstructure (S507400). The service information according to the presentinvention may include a service ID for identifying a service.

Subsequently, the receiver may determine whether or not the currentlyselected PLP group corresponds to the last PLP group (S507500).

Based upon the determined result, when it is determined that theselected PLP group does not correspond to the last PLP group, thereceiver may return to the process step S507300, so as to select thenext PLP group. Alternatively, when it is determined that the selectedPLP group corresponds to the last PLP group, the receiver may determinewhether or not the current channel corresponds to the last channel(S507600).

Then, based upon the determined result, when it is determined that thecurrent channel does not correspond to the last channel, the receivermay return to the process step S507100, so as to tune to the nextchannel. And, alternatively, when it is determined that the currentchannel corresponds to the last channel, the receiver may use the storedservice information so as to tune to a first service or a pre-setservice (S507700).

If the broadcasting signal receiving apparatus has the same structure asFIG. 26 or FIG. 49, as described above, the decoding of the PLPsincluding the L1 signaling information, the L2 signaling information,the PLPs transmitting the PSI/SI, and the PLPs including components maybe performed by at least one of the frame demapper, the BICM decoder,and the output processor. If the broadcasting signal receiving apparatushas the same structure as FIG. 37, the decoding of the PLPs includingthe L1 signaling information, the L2 signaling information, the PLPstransmitting the PSI/SI, and the PLPs transmitting components may beperformed by at least one of the frame demapper, the PLP deinterleavingand demodulator module, the L1 decoder, the BBF decoder, and the nullpacket reconfigurating module. Also, the scanning process may beperformed by a separate controller.

Second Embodiment (FIG. 54 to FIG. 56)

FIG. 54 illustrates a conceptual diagram of a correlation between aservice according to the second embodiment of the present invention anda PLP group.

The first embodiment of the present invention corresponds to a signalingmethod using a PLP Group ID and a service ID. And, in this case, thereceiver may use a correlation between a service and a PLP group one aservice level, so as to recover a service.

However, depending upon the characteristics of the receiver, when dataof an enhancement layer is to be selectively decoded so as to provide ahigh picture quality image, the signaling method according to the firstembodiment of the present invention is disadvantageous in that theinformation on a video stream, which is included in the PLP, cannot beacquired.

Therefore, according to the second embodiment of the present invention,when receiving a TS format broadcast signal, in addition to thesignaling method using the correlation between a service and a PLPgroup, a signaling method that can determine the type of the currenttransport stream and that can acquire information related to thecomponents included in each PLP, thereby being capable of selectivelyreceiving the transport stream and the PLP based upon the acquiredinformation.

As shown in FIG. 54, the L1 signaling information region 508100according to the second embodiment of the present invention may includediverse information related to each of the multiple PLPs, i.e., aPLP_GROUP ID field, a PLP_ID field, a PLP_COMPONENT_TYPE field, and soon. Also, the L2 signaling information region field 508200 may includean NTT and an SDT. Herein, the NIT may include a PLP_GROUP_ID field,which is identical to the PLP_GROUP_ID field included in the L1signaling information region 508100, and a transport_stream_id field. Byusing these fields, the receiver may be capable of knowing to which PLPgroup a specific transport stream is correlated. Also, the SDT mayinclude a transport_stream_id field, which is identical to thetransport_stream_id included in the NIT, and a service_id field. Byusing these fields, the receiver may be capable of differentiating (oridentifying) each of the services being transmitted through a specifictransport stream. Additionally, since the PMT include a program_numberfield, which matches with the service_id field included in the SDT, thereceiver may use the program_number field so as to verify a programnumber included in the selected service. Moreover, since the PMTincludes a stream type field, a PLP_ID field, and a PLP_COMPONENT_TYPEfield, the receiver may determine the type of the current stream byusing the stream type field. And, by using the PLP_COMPONENT_TYPE field,the receiver may determine the type of the component included in thecurrent PLP, so as to selectively receive the PLP.

Eventually, as described in the first embodiment of the presentinvention, the receiver may acquire the service_id field from the SDT,so as to be capable of identifying a desired service, among a pluralityof services included in a transmission frame. Then, by using the NIT,the receiver may identify a PLP group, which is related to a specifictransport stream transmitting the service. Thereafter, the receiver mayreceive a PLP having a PLP_GROUP_ID field included in the L1 signalinginformation, thereby being capable of recovering a service stream.Additionally, the receiver may also use the component informationincluded in the PLP, so as to selectively receive the PLP and to becapable of providing an image best-fitting the receiver characteristic.

Hereinafter, the fields, the NIT, and the SDT being included in the L1signaling information according to the second embodiment of the presentinvention will be described in detail.

Since the L1 signaling information according to the second embodiment ofthe present invention includes the same fields, which are included inthe L1 signaling information region described with reference to FIG. 48to FIG. 50, and since the NIT and the SDT are identical to the NIT andSDT described with reference to FIG. 51, detailed description of thesame will be omitted for simplicity. The PMT corresponds to a tableincluding information indicating or identifying the types of the streamsbeing included in each service or PID information for identifying thestreams.

The PMT according to the second embodiment of the present invention maybe transmitted through a PLP, and \ the transmitting end may process andtransmit the PMT as data. Furthermore, the PMT may also include aprogram_number field, and a PID loop.

Hereinafter, each field included in the PMT shown in FIG. 54 will bedescribed in detail.

A program_number field is used for identifying each program (or service)within the current transport stream. Herein, the program_number field ismatched with the service_id field of the SDT. The PID loop may includePID information (elementary_PID) of a TS packet to which individual bitstreams, such as video, audio, and so on, are being transmitted, whereinthe individual bit streams configure a program or (service), astream_type field, and a component_id_descriptor. Herein, the PIDinformation is a PID of a TS packet transmitting each stream, such asvideo, audio, and so on, configuring a program (or service). Astream_type field represents encoding information and a type of an ESwhich is included in a TS packet having a PID value that is expressed inthe elementary_PID field. Examples of the streams types according to thepresent invention may include an SVC stream, an AVC stream, and so on.

An elementary_PID field represents an identifier of an ES (ElementaryStream). That is, it is a field used for identifying a TS packettransmitting the ES.

A component_id_descriptor may include a PLP_ID field and aPLP_COMPONENT_TYPE field. Herein, since the PLP_ID field and thePLP_COMPONENT_TYPE field are identical to the PLP_ID field and thePLP_COMPONENT_TYPE field, which are included in the L1 signaling, adetailed description of the same will be omitted for simplicity.

Therefore, when multiple stream types exist, the receiver may identify aspecific stream by using the stream_type field and may select theidentified stream. Also, by using the PLP_COMPONENT_TYPE field, thereceiver may also determine whether the component being transmitted bythe PLP corresponds to a base layer or an enhancement layer, and thereceiver may then selectively decode the PLP of the enhancement layer inaccordance with the receiver characteristic.

FIG. 55 corresponds to an exemplary component_id_descriptor which isincluded in FIG. 54. Herein, the component_id_descriptor field is beingused for connecting the PLP_COMPONENT_TYPE field of the L1 signalinginformation region 508100 to the transport stream.

The component_id_descriptor may include a descriptor_tag field, adescriptor_length field, a system_id field, a PLP_ID field, and aPLP_COMPONENT_TYPE field. Herein, the PLP_ID field is used foridentifying a PLP that matches with a PID sub stream of thecorresponding stream type.

Since the contents of each field are identical to those described inFIG. 49 and FIG. 52, detailed description of the same will be omittedfor simplicity.

FIG. 56 illustrates a flow chart showing a service scanning method ofthe receiver according to a second embodiment of the present invention.

The receiver receives a broadcasting signal having a TS format and beingtransmitted to a specific channel via tuning (S510100). In this case, inorder to receive a service that is wanted (or desired) by the user,diverse information that can identify the service included in thetransmission frame, which is being transmitted through the channel, isrequired. Although this process is not shown in the drawing, thecorresponding process may be performed by the tuner of the receiver andmay be modified and varied in accordance with the intentions of thesystem designer.

Then, the receiver may decode the L1 signaling information included inthe transmission frame, so as to acquire a PLP ID, a PLP Group ID, and asystem ID, which are included in the transmission frame (S510200).Thereafter, the receiver may identify the PLP groups by using thedecoded PLP Group ID, so as to select the desired ELF group, and maydecode the PLP including the L2 signaling information and the PSI/SI(S510300). The receiver may decode the NIT and the SDT included in thedecoded L1 signal information, and the receiver may also decode aPAT/PMT included in the PLP, thereby being capable of storing serviceinformation associated with information on the structures of thetransmitting system and the PLP (S510400). The service informationaccording to the present invention may include a service ID foridentifying a service.

Additionally, the receiver may use the stream_type field and thePLP_COMPONENT_TYPE field included in the decoded PMT, so as to verifythe type of the component being transmitted by the current PLP, and thenthe receiver may store the component that is to be additionally receivedin accordance with the receiver characteristics (S510500). Morespecifically, the receiver may use the above-described stream_type andPLP_component_type information, so as to additionally receiver/store acomponent corresponding to the service, which may be provided inaccordance with the receiver characteristic.

Subsequently, the receiver may determine whether or not the currentlyselected PLP group corresponds to the last PLP group (S510600).

Based upon the determined result, when it is determined that theselected PLP group does not correspond to the last PLP group, thereceiver may return to the process step S510300, so as to select thenext PLP group. Alternatively, when it is determined that the selectedPLP group corresponds to the last PLP group, the receiver may determinewhether or not the current channel corresponds to the last channel(S510600).

Then, based upon the determined result, when it is determined that thecurrent channel does not correspond to the last channel, the receivermay return to the process step S510100, so as to tune to the nextchannel. And, alternatively, when it is determined that the currentchannel corresponds to the last channel, the receiver may use the storedservice information so as to tune to a first service or a pre-setservice (S510700).

If the broadcasting signal receiving apparatus has the same structure asFIG. 26 or FIG. 49, as described above, the decoding of the PLPsincluding the L1 signaling information, the L2 signaling information,the PLPS transmitting the PSI/SI, and the PLPS including components maybe performed by at least one of the frame demapper, the BICM decoder,and the output processor. If the broadcasting signal receiving apparatushas the same structure as FIG. 37, the decoding of the PLPs includingthe L1 signaling information, the L2 signaling information, the PLPStransmitting the PSI/SI, and the PLPs transmitting components may beperformed by at least one of the frame demapper, the PLP deinterleavingand demodulator module, the L1 decoder, the BBF decoder, and the nullpacket reconfigurating module. Also, the scanning process may beperformed by a separate controller.

Third Embodiment (FIG. 57 to FIG. 61)

FIG. 57 illustrates a conceptual diagram of a correlation between aservice according to the third embodiment of the present invention and aPLP group.

When a channel is scanned by the receiver according to the secondembodiment of the present invention, the receiver may not be capable ofscanning (or searching through) the entire PLP, which transmits thecomponents included in a single service. Since the components includedin each of the multiple services are transmitted through each PLP, a PLPthat does not include PSI/SI may also exist.

Therefore, in the third embodiment of the present invention, PSI/SI,such as the PAT/PMT, may be transmitted to a random PLP included in themultiple PLP regions, so that the entire PLP transmitting the componentsincluded in a single service can be scanned (or searched). As describedabove, in the description of the present invention, the PLP transmittingservice configuration information, such as the PAT/PMT, may also bereferred to as a base PLP. More specifically, when the receiver decodesthe base PLP, information on the remaining component PLPs included in asingle service may be acquired.

Eventually, according to the third embodiment of the present invention,instead of acquiring signaling information by processing all of the TS,by processing signaling information of the physical layer and byacquiring signaling information included in the base PLP, the signalinginformation respective to each PLP may be acquired.

As shown in FIG. 57, the L1 signaling information region 511100according to the third embodiment of the present invention may includeinformation respective to each of the multiple PLPs, i.e., a PLP_GROUPID field, a PLP_ID field, a PLP_COMPONENT_TYPE field, a PLP_PROFILEfield, and so on. Additionally, the 12 signaling information region511200 may include an NIT and an SDT. Herein, the NIT may include aBASE_PLP_ID field, which is matched with the PLP_ID field being includedin the L1 signaling information region 511100. And, by using theBASE_PLP_ID field, the receiver may identify a base PLP, which transmitsthe PMT/PAT. Furthermore, the SDT may include a transport_stream_idfield, which is identical to the transport_stream_id included in theNIT, and a service_id field. And, by using the SDT, the receiver maydifferentiate each of the services being transmitted through a specifictransport stream.

Additionally, since the PMT being transmitted through the base PLPinclude a program_number field, which is matched with the service_idfield included in the SDT, by using the program_number field, thereceiver may verify the program number included in the selected service.In addition, the PMT may include a stream_type field, a PLP_ID field,and a PLP_PROFILE field. In this case, by referring to the stream typefield included in the PMT, the receiver may recognize the type of thecurrent stream, and by using the PLP_ID field and the PLP_PROFILE filed,the receiver may determine the correlation between the PLP and thecomponent, thereby being capable of decoding the PLP best-fitting thePLP. More specifically, the receiver may use the PLP_PROFILE fieldincluded in the PMT, so as to perform decoding on the PLP, whichtransmits a distinguished service component, such as a standard picturequality service, high picture quality service, and so on, in accordancewith the characteristics of the receiver. Thus, the TS best-fitting thereceiver characteristics may be recovered.

Eventually, the receiver may identify and select the base PLP by usingthe BASE_PLP_ID field, which is included in the NIT, and the receivermay decode a PMT, which is transmitted through the base PLP.Additionally, the receiver may identify and select a wanted (or desired)service by using the service_id field, which is included in the SDT.Moreover, in addition to being capable of decoding all of the PLPs thatare included in a component, which is included in a single service, byusing the PLP_PROFILE field, the receiver may decode a PLP in accordancewith the receiver characteristic.

Hereinafter, the L1 signaling information region (511100), the NIT, theSDT, and the PMT according to the third embodiment of the presentinvention will be described in detail.

Since the L1 signaling information according to the third embodiment ofthe present invention is identical to the L1 signaling information shownin FIG. 48 to FIG. 50, a detailed description of the same will beomitted for simplicity.

The PLP_PROFILE field may identify whether the corresponding PLP is amandatory (or required) PLP or an optional (or selective) PLP. Forexample, in case the component being transmitted through the PLP isidentified (or distinguished) as a base layer or an enhancement layer,the PLP transmitting the base layer becomes the mandatory PLP, and thePLP transmitting the enhancement layer becomes the optional PLP.Particularly, the base PLP becomes the mandatory PLP. More specifically,depending upon the receiver characteristic, such as a mobile receiver, afixed-type receiver, and so on, the receiver may use the PLP_PROFILEfield so as to verify by which receiver the component of the broadcastservice being transmitted to the current PLP may be used, and dependingupon the receiver characteristic, the receiver may determine whether ornot to decode the current PLP.

The NIT according to the third embodiment of the present invention issimilar to the NIT according to the second embodiment of the presentinvention, which is described above with reference to FIG. 54. However,unlike the NIT according to the second embodiment of the presentinvention, the NIT according to the third embodiment of the presentinvention may further include a BASE_PLP_ID field.

Herein, the BASE_PLP_ID field is used for identifying the base PLP. And,the base PLP may transmit PSI/SI information of a corresponding service,such as the PMT/PAT. Additionally, the BASE_PLP_ID field may be includedin a delivery_system_descriptor of the NIT.

The PMT according to the third embodiment the present invention mayinclude a program_number field and a PID loop. And, the PID loop mayinclude a stream_type field and a component_id_descriptor. Herein, thecomponent_id_descriptor may include a PLP_PROFILE field and a PLP_IDfield. The contents of the program_number field and the PLP_ID field areidentical to those described above with reference to FIG. 49 and FIG.54. And, since the PLP_PROFILE field is identical to the PLP_PROFILEfield included in the L1 signaling information, a detailed descriptionof the same will be omitted for simplicity.

FIG. 58 illustrates an exemplary delivery system descriptor included inthe NIT of FIG. 57.

As shown in FIG. 58, the delivery_system_descriptor according to thethird embodiment of the present invention is identical to thedelivery_system_descriptor according to the first embodiment of thepresent invention, which is shown in FIG. 52. However, unlike thedelivery_system_descriptor according to the first embodiment of thepresent invention, the delivery_system_descriptor according to the thirdembodiment of the present invention may further include a BASE_PLP_IDfield. Since the description of the BASE_PLP_ID field is identical tothat of FIG. 57, a detailed description of the same will be omitted forsimplicity.

FIG. 59 illustrates an exemplary component ID descriptor included in thePMT of FIG. 57.

As shown in FIG. 59, the component_id_descriptor, which is included inthe PID loop of the PMT according to the third embodiment of thepresent, is identical to the component_id_descriptor according to thesecond embodiment of the present invention, which is shown in FIG. 54.However, the component_id_descriptor according to the third embodimentof the present invention may include a PLP_PROFILE field instead of thePLP_COMPONENT_TYPE field. Herein, since the description of thePLP_PROFILE field is identical to that of FIG. 57, a detaileddescription of the same will be omitted for simplicity.

FIG. 60 illustrates an exemplary PLP_PROFILE field according to thethird embodiment of the present invention.

As shown in FIG. 60, the PLP_PROFILE field may provide information in abit-unit selector format.

The PLP_PROFILE field may indicate information on a video component inaccordance with the field value. For example, when the field value isequal to 0x00, this signifies a common profile and indicates that thevideo component corresponds to a component that can be received and usedby any receiver. When the field value is equal to 0x01, this indicatesthat the video component corresponds to a component that can be usedonly by mobile receivers, and when the field value is equal to 0x02,this indicates that the video component corresponds to an HD profilecomponent that can be used only by HD receivers (or fixed receivers).And, when the field value is equal to 0x03, this indicates that thecomponent can be applied to both mobile receivers and HD receivers.

FIG. 61 illustrates a flow chart showing the process steps of a servicescanning method of the receiver according to the third embodiment of thepresent invention.

The receiver receives a broadcasting signal having a TS format viatuning (S515100). In this case, in order to receive a service that iswanted (or desired) by the user, diverse information that can identifythe service included in the transmission frame, which is beingtransmitted through the channel, is required. Although this process isnot shown in the drawing, the corresponding process may be performed bythe tuner of the receiver and may be modified and varied in accordancewith the intentions of the system designer.

The receiver decodes the L1 signaling information included in thetransmission frame, so as to acquire a PLP ID, a PLP group ID, PLPcomponent type information, PLP profile information, system ID, and soon (S515150). Thereafter, the receiver identifies the PLP groups basedupon the decoded PLP group ID, so as to select a wanted (or desired) PLPgroup, and then decodes the L2 signaling information (S515200).Additionally, the receiver decodes the NIT included in the L2 signalinginformation and uses the BASE_PLP_ID field included in the NIT, so as tofind and locate the base PLP of each service (S515250). Subsequently,the receiver may use the transport_stream_id field, which is included inthe NIT, so as to identify the transport stream included in the PLPgroup and to decode the PMT included in the base PLP (S515300). Thereceiver may use the PLP_PROFILE field, which is included in a componentID descriptor field of the decoded PMT, so as to verify which receivermay use the component of the broadcast service, which is beingtransmitted to the current PLP in accordance with the receivercharacteristic, such as mobile receiver, HD receiver, and so on.Accordingly, by using the PLP_ID field, the receiver may selectivelydecode the PLP that is requested to be decoded.

Thereafter, the receiver may store the information related to thecorrelation between the component and the PLP, based upon the receivercharacteristic (S515350). The information related to the correlationbetween the component and the PLP may include the PID information of thePMT and the PLP_id included in the component_ID_descriptor.

Subsequently, the receiver may determine whether or not the current TScorresponds to the last TS within the PLP group (S515400).

When it is determined that the current TS does not correspond to thelast TS, the receiver may return to the process step S515250, so as toparse the NIT and to acquire the base PLP by using the BASE_PLP_IDfield. Alternatively, when it is determined that the current TScorresponds to the last TS, the receiver may determine whether or notthe current PLP group corresponds to the last PLP group (S515450).

When it is determined that the selected PLP group does not correspond tothe last PLP group, the receiver may return to the process step S515200,so as to select the next PLP group and to decode a base PLP.Alternatively, when it is determined that the selected PLP groupcorresponds to the last PLP group, the receiver may determine whether ornot the current channel corresponds to the last channel (S515500).

Thereafter, when it is determined that the current channel does notcorrespond to the last channel, the receiver may return to the processstep S515100, so as to tune to the next channel. And, alternatively,when it is determined that the current channel corresponds to the lastchannel, the receiver may tune to a first service or a pre-set service(S515550).

If the broadcasting signal receiving apparatus has the same structure asFIG. 26 or FIG. 49, as described above, the decoding of the PLPsincluding the L1 signaling information, the L2 signaling information,the PLPs transmitting the PSI/SI, and the PLPs including components maybe performed by at least one of the frame demapper, the BICM decoder,and the output processor. If the broadcasting signal receiving apparatushas the same structure as FIG. 37, the decoding of the PLPs includingthe L1 signaling information, the L2 signaling information, the PLPstransmitting the PSI/SI, and the PLPs transmitting components may beperformed by at least one of the frame demapper, the PLP deinterleavingand demodulator module, the L1 decoder, the BBF decoder, and the nullpacket reconfigurating module. Also, the scanning process may beperformed by a separate controller.

Fourth Embodiment (FIG. 62 to FIG. 64)

FIG. 62 illustrates a conceptual diagram of a correlation between aservice according to the fourth embodiment of the present invention anda PLP group.

In case of transmitting a broadcast signal of a IP format, the fourthembodiment of the present invention corresponds to a signaling methodfor recovering a transport stream by acquiring a service IP address andinformation on a component type and information on a component address,which are included in a PLP, and by merging multiple PLPs being includedin the same PLP group.

As shown in FIG. 62, the L1 signaling information region 516100according to the fourth embodiment of the present invention may includeinformation related to each of the multiple PLPs, i.e., a PLP_GROUP IDfield, a PLP_ID field, and so on. Also, the L2 signaling informationregion 516200 may include an IP information table, and the IPinformation table may include a IP_address_list( ) field and adescriptor. The IP_address_list( ) field may include IP addressinformation for receiving a Bootstrap, and the descriptor may includethe same PLP_GROUP_ID field and PLP_ID field that are included in the L1signaling information region 516100. Since the IP_address_list( ) fieldand the descriptor form a pair, by using this pair, the receiver may becapable of knowing which PLP group is correlated to a specific IPstream. Thereafter, the receiver may use the IP_address_list( ) field,so as to receive Bootstrap information. Herein, the bootstrapinformation includes a boot_IP_address field. And, by using theboot_IP_address field, the receiver may acquire an IP address that canreceiver (or acquire) a service guide information or broadcast contentguide information.

Subsequently, by using the received bootstrap information, the receivermay receiver service guide information, such as ESG (Electronic ServiceGuide)/BCG (Broadcast Contents Guide). The service guide information orbroadcast contents guide information may be transmitted through aninteractive channel and may be received through an IP stream, which isincluded in a specific PLP. This may vary depending upon the intentionsof the system designer. The receiver may use the service_id field, thecomponent_type field, and the component_IP_address field, which areincluded in the ESG/BCG, so as to decode a desired (or wanted) serviceand service components.

Eventually, by using the component_IP_address included in the ESG/BCG,or by using the boot_IP_address field of the bootstrap, the receiver mayacquire an IP address for each service and service components. And, byusing the IP_address_list( ) field and the PLP_GROUP_ID field of the IPinformation table, the receiver may be capable of knowing which IPstream/packet is correlated to the PLP group. Thereafter, the receivermay merge the service components that are included in a PLP having thesame PLP_GROUP_ID field included in the L1 signaling information region516100, so as to recover a service.

Hereinafter, the L1 signaling information, the IP information table, abootstrap, and an ESG/BCG will be described in detail.

The L1 signaling information according to the fourth embodiment of thepresent invention may include the same fields included in the L1signaling information, which is described in FIG. 48 to FIG. 50. And,the receiver may use the PLP_COMPONENT_TYPE field so as to determinewhether or not the L1 signaling information is matched with thecomponent_type field included in the ESG/BCG.

The IP information table according to the fourth embodiment of thepresent invention corresponds to a table include IP-related information,i.e., information on an IP address and so on. Herein, the receiver maybe capable of knowing how the IP stream is being transmitted from the IPinformation table through the transport stream.

The IP information table may include an IP_addr_location loop, and theIP_addr_location loop may include a target_IP_add_descriptor( ) and anIP/MAC_location_descriptor.

The target_IP_add_descriptor( ) may include an IP_address_list( ) field,and the IP_address_list( ) field may include information related to theIP address. According to the embodiment of the present invention, thepresent invention includes an IP address/port field. Depending upon thenumber of ports, a plurality of the IP address/port fields may beincluded. The IP/MAC_location_descriptor may also be referred to as anIP/MAC_location_information field, which may be used for connecting thePLP_COMPONENT_TYPE field included in the L1 signaling information to theIP stream. The IP/MAC_location_descriptor may include the same PLP_IDfield and PLP_GROUP_ID field as the PLP_ID field and the PLP_GROUP_IDfield, which are included in the L1 signaling information.

Hereinafter, each field included in the bootstrap and ESG/BCG shown inFIG. 62 will be described in detail.

Herein, the Bootstrap may include a boot_IP_addr field, and theboot_IP_addr field may identify a booting address of the IP.

The ESG/BCG may include a NUM_SERVICE loop. Herein, the NUM_SERVICE loopmay include a respective service_name field, service_id field, and aNUM_COMPONENT loop for each of the multiple services.

The service_name field may be used for indicating the name of eachservice, and the service_id field may be used for identifying eachservice.

The NUM_COMPONENT loop corresponds to a loop include information on themultiple components, which are included in a service. Herein, theNUM_COMPONENT loop may include a component_type field and acomponent_IP_address field.

The component_type field may be used for identifying component types ofthe service. And, examples of the components according to the presentinvention may include a video component of the base layer, a videocomponent of the enhancement layer, audio components, data components,and so on. Also, the component_type field may be matched with thePLP_COMPONENT_TYPE field, which is included in the L1 signalinginformation.

The component_IP_address field may identify the IP address of eachcomponent.

FIG. 63 illustrates an exemplary IP/MAC_location_descriptor according tothe fourth embodiment of the present invention.

As shown in FIG. 63, the IP/MAC_location_descriptor according to thefourth embodiment of the present invention may include the same fieldsas the component_id_descriptor field according to the second embodimentof the present invention, which is described above with reference toFIG. 55. Herein, however, the IP/MAC_location_descriptor according tothe fourth embodiment of the present invention may include aPLP_GROUP_ID field instead of the PLP_COMPONENT_TYPE field. Since thedescription of each field is identical to that of FIG. 49 and FIG. 55,detailed description of the same will be omitted for simplicity.

FIG. 64 illustrates a flow chart showing the process steps of a servicescanning method of the receiver according to the fourth embodiment ofthe present invention.

The receiver tunes to receive an IP type broadcast signal (S518100). Inthis case, in order to receive a service desired by the user, thereceiver requires information on the service included in thetransmission frame, which is being transmitted through the respectivechannel. Although this process step is not shown in the drawing, thisprocess step may be performed by the tuner of the receiver and may bemodified or varied in accordance with the intentions of the systemdesigner.

Then, the receiver may decode the L1 signaling information included inthe transmission frame, so as to acquire a PLP ID and a PLP Group ID(S518200). Thereafter, the receiver may identify the PLP groups by usingthe decoded PLP group ID so as to select a desired PLP group, and thereceiver may then decode the L2 signaling information and the PLPincluding the PSI/SI and metadata (S518300).

The receiver may decode the IP information table included in the decodedL2 signaling information, and the receiver may also decode the metadataincluded in the PLP (S518400). Additionally, the receiver may acquireservice information associated with information on the transmittingsystem and PLP structures, thereby being capable of storing the acquiredservice information (S518400). The service information according to thepresent invention may include a service IP address, a component IPaddress, and so on. Subsequently, the receiver may determine whether ornot the currently selected PLP group corresponds to the last PLP group(S518500).

Based upon the determined result, when it is determined that theselected PLP group does not correspond to the last PLP group, thereceiver may return to the process step S518300, so as to select thenext PLP group. Alternatively, when it is determined that the selectedPLP group corresponds to the last PLP group, the receiver may determinewhether or not the current channel corresponds to the last channel(S518600).

Then, based upon the determined result, when it is determined that thecurrent channel does not correspond to the last channel, the receivermay return to the process step S518100, so as to tune to the nextchannel. And, alternatively, when it is determined that the currentchannel corresponds to the last channel, the receiver may use the storedservice information so as to tune to a first service or a pre-setservice (S518700).

If the broadcasting signal receiving apparatus has the same structure asFIG. 26 or FIG. 49, as described above, the decoding of the PLPsincluding the L1 signaling information, the L2 signaling information,the PLPS transmitting the PSI/SI and metadata, and the PLPs includingcomponents may be performed by at least one of the frame demapper, theBICM decoder, and the output processor. If the broadcasting signalreceiving apparatus has the same structure as FIG. 38, the decoding ofthe PLPS including the L1 signaling information, the L2 signalinginformation, the PLPS transmitting the PSI/SI, and the PLPs transmittingcomponents may be performed by at least one of the frame demapper, thePLP deinterleaving and demodulator module, the L1 decoder, the BBFdecoder, and the null packet reconfigurating module. Also, the scanningprocess may be performed by a separate controller.

Meanwhile, the present invention proposes a method for reducing anoverhead of a data packet, when IP based data are transmitted based.According to the embodiment of the present invention, by compressing andtransmitting the header of a data packet, the present invention mayreduce the overhead of a data packet. Additionally, according to theembodiment of the present invention, whether or not compression is beingapplied to the header of the data packet may be signaled to at least oneof the L1 signaling information and the L2 signaling information.Furthermore, according to the embodiment of the present invention, whenthe data packet header is compressed, the compression information of thedata packet header, which is required by the receiver for performingdecompression on the header of the compressed data packet, is signaledto at least one of L1 signaling information and L2 signalinginformation.

According to the embodiment of the present invention, among the headercompression methods, the header of a data packet is compressed by usinga RoHC (Robust Header Compression) method. The RoHC method is merely anexample given to facilitate the understanding of the present invention.And, therefore, any other method for compressing a header may be appliedherein.

Most particularly, according to the embodiment of the present invention,among the compressed data packet header information, a portion of thecorresponding information may be transmitted to a common PLP.

In the present invention, a data packet is largely configured of aheader and a payload. Herein, the header includes information requiredfor transmitting the data packet (e.g., transmitter information,receiver information, port number, data size, error correction code, andso on), and the payload include data that are to be actuallytransmitted. At this point, depending upon the type of data beingtransmitted to the payload, and a protocol being used for packetization,the header of the data packet may be configured of an IP header and aUDP header, and the header of the data packet may also be configured ofan IP header, a UDP (or TCP) header, and an RTP header.

For example, if a UDP packet is packetized in accordance with an IPmethod, after the data being transmitted to the payload (e.g., A/V data)have been packetized by using the RTP method, and after the RIP packethas been packetized once again by using the UDP method, the data packetis configured of an IP header, a UDP header, an RTP header, and apayload. However, this is merely an example, and other types of headerconfigurations may be applied to the present invention. In thedescription of the present invention, the data packet may also bereferred to as an IP packet.

FIG. 65 illustrates an IP header configuring a header of a data packetaccording to an embodiment of the present invention.

The IP header includes an IP version field indicating an IP protocolversion, such as IPv4, IPv6, and so on, an Internet Header Length (IHL)field indicating the length of an IP header, a TOS (Type of Service)field indicating priority information respective to the service type, aTotal Length field indicating a total length of the corresponding datapacket, a packet identifier (Identification) field, an IP fragment flags(IP Flags) field indicating information on data segments (or fragments)of an IP layer, a Fragment Offset field indicating a relative positionof the segmented (or divided) packets, a TTL (Time to Live) fieldindicating time information up to when the data are deleted, a higherlayer Protocol field indicating a protocol (TCP, UDP, and so on) that isused in the higher layer, a Header Checksum field checking for an errorin the header, a source IP address field indicating an IP address of asource device, and a destination (or target) IP address field indicatingan IP address of a destination (or target) device.

FIG. 66 illustrates an UDP header configuring a header of a data packetaccording to an embodiment of the present invention.

The UDP header includes a source port number field indicating a portnumber of a source device, a destination (or target) port number fieldindicates a port number of a destination (or target) device, a fieldlength indicating a total length of the corresponding data field, and achecksum filed for certifying the reliability of the corresponding datapacket.

For example, when the header part of the data packet includes an IPheader, a UDP header, and an RTP header, and when the IP versioncorresponds to IPv4, the overhead of the header included in the datapacket becomes equal to 40 bytes. However, such an overhead may cause acritical problem in a wireless system, wherein the bandwidth is limited.At this point, when the header of the data packet is compressed by usingthe RoHC method, the overhead may be reduced to 1 byte or 3 bytes. Morespecifically, the transmitting end compresses and transmits at least oneof the IP/UDP/RTP headers within the data packet, and the receiverdecompressed the header of the received data packet, thereby recoveringthe IP/UDP/RTP headers prior to being compressed.

(a) and (b) of FIG. 67 illustrates conceptual diagrams of an RoHCcompression algorithm according to the present invention. Herein, (a) ofFIG. 67 shows an example of the data packets prior to being compressedand (b) of FIG. 67 shows an example of the data packets being compressedby using the RoHC method. Although a payload exists in each packet in(a) and (b) of FIG. 67, the present invention will only describe theheader of the data packets.

For simplicity in the description of the present invention, the packetprior to being compressed will hereinafter be referred to as a datapacket, and the packet being compressed by using the RoHC method willhereinafter be referred to as an RoHC packet (or header-compressed datapacket).

In the RoHC compression method, the overall headers of the data packetconfiguring the IP stream, which is identified by the IP addressinformation, may be indicated by a single context identifier (ContextID). Herein, at the beginning of the transmission, the overall header istransmitted. Then, as the transmission progresses, the compressionprocess is processed by using a method of remaining only the Context IDand the essential information and omitting the non-varying parts.

According to an embodiment of the present invention, when performing IPstreaming, among the information included in the IP header and the UDPheader of FIG. 65 and FIG. 66, IP version, source IP address,destination IP address, IP fragment flag, source port number,destination port number, and so on, hardly varies (or changes) duringthe streaming process. In the description of the present invention, thefields transmitting information that hardly changes during the streamingprocess, as described above, will be referred to as static fields.

In the RoHC compression method, information on such static fields istransmitted only once and is not additionally transmitted for apredetermined period of time. This is referred to as an Initializationand Refresh (hereinafter referred to as IR) state, and a data packethaving the static field information transmitted to the header isreferred to as an IP packet. Moreover, information on dynamic fields,which consistently changes yet maintains the same state for apredetermined period of time, are separately scheduled to performedadditional transmission. Herein, a data packet having the dynamic fieldinformation transmitted to its header is referred to as an IR-DYNpacket. According to the embodiment of the present invention, the IRpacket also includes dynamic field information. Since the IR packet andthe IR-DYN packet carry all information of the conventional header, theIR packet and the TR-DYN packet have a similar size as the conventionalheader. More specifically, among the header information of the datapacket, the static field information may be transmitted at the beginningthrough the IR packet, and the dynamic field information is transmittedeach time the information is updated through the IR-DYN packet.

In addition to the IR packet and the IR-DYN packet, the data packethaving its header compressed may further include a first order (FO) anda second order (SO). The FO packet and the SO packet are configured onlyof 1-2 byte information. The FO packet compresses and transmits allstatic field information and most of the dynamic field information, andthe SO packet periodically compresses and transmits all of the dynamicfield information.

As described above, in the RoHC compression method, IR packets includingthe static and dynamic field information are transmitted only whenrequired, and, in the remaining cases, the FO packets or SO packets,which are configured only of the 1-2 byte information, are transmitted.Thus, 30 bytes or more of the overhead may be reduced for each datapacket.

However, when such RoHC compression method is adopted, in a broadcastingnetwork that does not have any return channels, the receiver isincapable of knowing at which point the IP stream is to be received.And, a general receiver may not be capable of recognizing thecorresponding data packet.

In order to resolve such problems, the present invention transmitscompression information of the data packet header by signaling thecorresponding compression information to the L1 signaling informationand the L2 signaling information. According to the embodiment of thepresent invention, the present invention signals and transmits thecompression information to the L2 signaling information. The L2signaling information corresponds to the signaling information beingtransmitted to the common PLP.

Additionally, according to the embodiment of the present invention,header information of an IR packet, which is referred to when performinginitialization/information update, is transmitted to the common PLP. Atthis point, all of the header information of the IR packet may betransmitted to the common PLP, or only a portion of the headerinformation may be transmitted to the common PLP. In this case, theremaining portion of the header information may be transmitted to thedata PLP. For example, among the header information of the IR packet,the static field information may be transmitted to the common PLP, andthe dynamic field information may be transmitted to the data PLP.

More specifically, the data packets, which are compressed by using theRoHC method, may be recovered by the receiver to the state prior to beprocessed with compression, only when the header information of the IRpacket exists. However, a broadcasting network that does not have anyreturn channel is incapable of knowing when the IR packet is beingreceived. Therefore, in order to constantly receive the headerinformation of the IR packet, only the header information of the IRpacket is transmitted to a separate common PLP.

Meanwhile, according to the embodiment of the present invention, thecompression information being signaled to the L2 signaling informationincludes at least one of information indicating a compression method ofthe data packet header, context profile information, and contextidentifier information.

The information indicating a compression method of the data packetheader will also be referred to as a header compression type(header_compression_type). According to the present invention, when theheader_compression_type field value is equal to 0, this may signify thatthe header of the data packet is not compressed (no compression), and,when the header_compression_type field value is equal to 1, this maysignify that the header of the data packet is compressed by using theRoHC method.

According to the embodiment of the present invention, the contextprofile information will be referred to as a context profile(context_profile) field, which indicates up to which protocol (or whichlayer) the compression has been performed, when performing compressionon the header of the data packet. According to the embodiment of thepresent invention, when the context_profile field value is equal to 0,this may indicate that the data packet has an RoHC compression packetyet that the actual header information has not been compressed. And,when the context_profile field value is equal to 1, this may indicatethat the header of the data packet has been compressed by using the RoHCmethod up to the RTP, up to the UDP, when the context_profile fieldvalue is equal to 2, up to the ESP, when the context_profile field valueis equal to 3, and up to the IP, when the context_profile field value isequal to 4.

The context identifier information will also be referred to as a contextidentifier (context_id) field, which represents a context identifieridentifying that the header of the data packet has been compressed. Whenthe receiver groups and processes compressed data packets having thesame context identifier, an IP stream may be configured.

Most particularly, according to the embodiment of the present invention,among the L2 signaling information being transmitted to the common PLP,the compression information is signaled to the IP information table. Thecompression information may be included in a field format within the IPinformation table, and may also be included in a specific descriptor ofthe IP information table. The compression information may be included ina field format even when being included in the specific descriptor.

The IP information table may correspond to an INT (IP/MAC notificationtable), which signals IP-PLP mapping information, and may correspond toanother table. Additionally, an IP information table may be divided intosection units, and the compression information may be signaled to onesection.

FIG. 68 shows an example of the compression information being signal toan IP/MAC_location_descriptor( ) of the IP information table.Additionally, the IP/MAC_location_descriptor( ) signals PLP informationthat matched with an IP stream, which is delivered to an IP address/portnumber being signals to a target_IP_address_descriptor( ). Forsimplicity in the description of the present invention, PLP informationbeing matched with an IP address/port number of the IP stream and the IPstream will also be referred to as IP-PLP mapping (or link) information.According to the embodiment of the present invention, the PLPinformation includes at least one of a PLP profile (plp_profile), a PLPidentifier (plp_id), and a system identifier. The PLP information mayfurther include a PLP group identifier (plp_group_id).

The IP table information of FIG. 68 may correspond to the same table asthe IP information table shown in FIG. 62, or may correspond to anothertable. Herein, since a target_IP_address_descriptor( ) and anIP/MAC_location_descriptor( ) form a pair, by using this descriptorpair, the receiver may be capable of knowing to which PLP a specific IPstream is associated, and the descriptor pair may also gain compressioninformation of the specific IP stream. Furthermore, based upon theacquired (or gained) compression information, the descriptor pair mayperform decompression of the specific IP stream.

According to the embodiment of the present invention, theIP/MAC_location_descriptor( ) includes a plp_profile field, a plp_idfield, a system_id field, a header_compression_type field, acontext_profile field, and a context_id field.

Since the plp_profile field and the plp_id field are identical to theplp_profile field and the plp_id field included in the L1 signalinginformation of FIG. 49, detailed description of the same will be omittedfor simplicity. More specifically, the plp_profile field and the plp_idfield correspond to mapping (or link) information for connected the L1signaling information and the L2 signaling information.

FIG. 69 illustrates a syntax structure providing a more detaileddescription of the IP/MAC_location_descriptor( ) shown in FIG. 68.

Referring to FIG. 69, according to the embodiment of the presentinvention, a descriptor_tag field is assigned with 8 bits and indicatesthat the corresponding descriptor is an IP/MAC_location_descriptor( ).

A descriptor_length field is assigned with 8 bits and indicates the sizewithin the corresponding descriptor starting from this field up to thelast field.

A descriptor_tag_extension field is assigned with 8 bits and indicatesadditional information enabling the corresponding descriptor to beidentified as the IP/MAC_location_descriptor( ).

A plp_profile field is assigned with 8 bits and may identify whether thecorresponding PLP is a mandatory PLP or an optional PLP. The receivermay use the plp_profile field so as to determine in which receiver thecomponent being transmitted to the current PLP is to be transmitted,based upon the receiver characteristic, such as mobile receiver,fixed-type receiver, and so on. And, then the receiver may determinewhether or not to decode the current PLP based upon the receivercharacteristic.

A plp_id field is assigned with 8 bits and indicates an identifier foridentifying the corresponding PLP.

A system_id field is assigned with 16 bits and corresponds to a fieldthat is used for identifying a broadcasting network specific system.

A header_compression_type field is assigned with 8 bits and indicateswhether or not the header has been compressed. According to theembodiment of the present invention, when the header_compression_typefield value is equal to 0, this indicates that compression has not beenperformed on the header (no compression), and, when theheader_compression_type field value is equal to 1, this indicates theheader has been compressed by using the RoHC method.

A context_profile field is assigned with 8 bits and indicates up towhich protocol (or which layer) the compression has been performed, whenperforming compression on the header of the data packet. According tothe present invention, when the context_profile field value is equal to0, this may indicate that the data packet has an RoHC compression packetyet that the actual header information has not been compressed. And,according to the embodiment of the present invention, when thecontext_profile field value is equal to 1, this may indicate that theheader of the data packet has been compressed by using the RoHC methodup to the RTP, up to the UDP, when the context_profile field value isequal to 2, up to the ESP, when the context_profile field value is equalto 3, and up to the IP, when the context_profile field value is equal to4.

The context_id field is assigned with 8 bits and indicates a contextidentifier for identifying that the header of the data packet has beencompressed.

As described above, the header information of the IR packet may betransmitted to the common PLP. At this point, the header information ofthe IR packet may be collectively signaled and transmitted to an IPinformation table to which compression information is being transmitted,or the header information of the IR packet may be signaled andtransmitted to another table.

When the header information of the IR packet is signaled to a tableother than the IP information table, the corresponding table will bereferred to as an IRT (Initiation & Refresh Table).

As shown in FIG. 68, the IRT according to the present invention includesan IR_packet_header_byte( ) field, which is repeated as many times asthe values of the context_profile field, the context_id field, and theheader_length field, so as to transmit the header information of the IRpacket.

The header_length field indicates the size of the header information ofthe IR packet, which is being transmitted to the IR_packet_header_byte().

The context_profile field and the context_id field are respectivelyassigned with the same values of each of the context_profile field andthe context_id field, which are signaled to theIP/MAC_location_descriptor( ) of the IP information table. Morespecifically, the context profile and the context identifier correspondto mapping (i.e., link) information connecting the IP information tableto the IRT. Therefore, the receiver may use the context profile and thecontext identifier, so as to be capable of acquiring compressioninformation of a specific IP stream from the IP information table andacquiring IR packet header information from the IRT. The presentinvention may also use only the context identifier, so as to connect theIP information table and the IRT.

The header information of the IR packet being transmitted to theIR_packet_header_byte( ) field may include both the static fieldinformation and the dynamic field information, or may include any one ofthe static field information and the dynamic field information. Forexample, the static field information may be transmitted to theIR_packet_header_byte( ) field and the dynamic field information may betransmitted to the corresponding component PLP.

Meanwhile, the header information of the IR packet may be signaled tothe IP information table along with the compression information.

As another embodiment of the present invention, FIG. 70 illustrates asyntax structure of an IP information table having header information ofan IR packet be signaled along with compression information. Accordingto the embodiment of the present invention, theIP/MAC_location_descriptor( ) of the IP information table shown in FIG.70 includes a plp_profile field, a plp_id field, a system_id field, aheader_compression_type field, a context_profile field, a context_idfield, and an IR_packet_header_byte( ) field. More specifically, headerinformation of the IR packet exists in each context.

For the description of each field shown in FIG. 70, reference may bemade to the description of the fields having the same title shown inFIG. 62 and FIG. 68. Therefore, the detailed description of the samewill be omitted for simplicity.

As shown in FIG. 70, if the compression information and the headerinformation of the IR packet are collectively transmitted through the IPinformation table, the receiver is not required to additionally searchfor the header information of the IR Packet. However, the size of the IPinformation table may become larger.

FIG. 71 illustrates a syntax structure showing theIP/MAC_location_descriptor( ) of FIG. 70 in more detail. Herein, anIR_packet_header_byte( ) field, which is repeated as many times as thevalue of the header length (header_length) field, so as to transmitheader information of the IR packet, is added to theIP/MAC_location_descriptor( ) shown in FIG. 69. With the exception forsuch addition of the IR_packet_header_byte( ) field, theIP/MAC_location_descriptor( ) of FIG. 70 is identical to theIP/MAC_location_descriptor( ) shown in FIG. 69.

The present invention may signal compression information to the L1signaling information, so that the receiver can respond to thecompressed IP stream.

At this point, the compression information may be signaled to the L1signaling information by adding a new field in the L1 signalinginformation.

According to an embodiment of the present invention, a PLP_PAYLOAD_TYPEfield, which indicates the type of a PLP payload, is used foradditionally signaling the compression information. For example, IPcompressed and GSE compressed modes are added to the PLP_PAYLOAD_TYPEfield, so that the receiver can identify whether the type of the dataincluded in the PLP payload corresponds to any one of GFPS, GCS, GSE,TS, IP, IP compressed, and GSE compressed, by referring to thePLP_PAYLOAD_TYPE field. By performing such signaling, the receiver maybe capable of identifying whether or not a stream, which is extractedduring the decoding of the PLP, has been compressed, thereby beingcapable of determining whether or not a decompressing unit (or RoHCdecoder) should be applied.

According to the embodiment of the present invention, theabove-described compression of the header included in the data packet isperformed by the input pre-processor of the broadcast transmittingapparatus. In the description of the present invention, a block that isused for compressing the header of the data packet will be referred toas a header compressing unit (or RoHC encoder).

If the header compressing unit is applied to the input pre-processorshown in FIG. 11, the header compressing unit may be provided at theinputting end of the UDP/IP filter (106010), or may be provided at theoutputting end of the UDP/IP filter (106010). In case the headercompressing unit is provided at the inputting end of the UDP/IP filter(106010), an IP stream corresponding to a service is inputted to theheader compressing unit, wherein the header included in each data packetconfiguring the IP stream is compressed. Thereafter, theheader-compressed data packets are inputted to the UDP/IP filer(106010), so as to be filtered for each component. At this point, if thebroadcast receiving apparatus of FIG. 38 is used, the headerdecompressing (or decompression) unit, which performs decompressing onthe header-compressed data packets, may be provided at the outputtingend of the buffer unit (220700). Herein, the header decompressing unitincludes an RoHC decoder.

In another example, if the header compressing unit is provided at theoutputting end of the UDP/IP filter (106010), the header compressingunit performs header compression on the data packets, which are filteredfor each component. In this case, the header decompressing unit of thereceiver may be provided between the BBF decoder (220600) and the bufferunit (220700).

At this point, among the data packets that are header-compressed by theheader compressing unit, the header information of the IR-DYN packet, FOpacket, and SO packet are transmitted through the correspondingcomponent PLP. Conversely, among the compressed packets, at least aportion of the header information included in the IR packet istransmitted through a common PLP. At this point, the data beingtransmitted to the payload of the IR packet may be transmitted throughthe corresponding component PLP. If only a portion of the headerinformation included in the IR packet is transmitted to the common PLP,the remaining header information may be transmitted through thecorresponding component PLP. And, the compression information istransmitted through the common PLP.

FIG. 72 illustrates a block diagram showing the structure of a portionof an input-pre-processor, which is used for compressing data packets,according to an embodiment of the present invention. Herein, FIG. 72shows an example wherein a header compressing unit is provided as theoutputting end of the UDP/IP filter (106010).

Referring to FIG. 72, a number of header compressing units(700301˜700304) corresponding to the number of common PLPs and componentPLPs is provided as the outputting end of the UDP/IP filter (106010), sothat compression may be performed on the header of the correspondingdata packet, which is being filtered from the UDP/IP filter (106010), byusing the RoHC method.

At this point, among the compressed data packets, each of the headercompressing units (700301˜700304) outputs header information of the IRpacket and compression information to an information merger (700200),and, then, each of the header compressing units (700301˜700304) outputsheader information of the IR_DYN, FO, and SO packets to the respectiveGSE encapsulating module, so that the corresponding header informationcan be transmitted to the respective component PLP. Herein, the GSEencapsulating module is optional. And, a component merger may be furtherincluded at the inputting end or the outputting end of each of theheader compressing units (700301˜700304). Reference may be made to FIG.11 for the detailed description of the component merger, and, therefore,a detailed description of the same will be omitted herein.

Furthermore, an IP service controller, an IP service informationdecoder, an IP service information correcting/generating module, and anIP stream merger are also provided in FIG. 72. However, thecorresponding blocks are not shown in the drawing. Reference may be madeto FIG. 11 for the detailed description of each block.

At this point, an IP-PLP link information generating unit (700100)generates IP-PLP mapping information, which includes an IP address/portnumber transmitting each IP stream and PLP information matching with theIP stream. The information merger (700200) merges the IP-PLP mappinginformation, which is generated by the IP-PLP link informationgenerating unit (700100), with the compression information beingoutputted from each header compressing unit (700301˜700304) and theheader information of the IR packet. Thereafter, the information merger(700200) outputs the merged information to the TS encapsulating module(700400), thereby signaling the merged information to at least one table(or section) of the L2 signaling information.

Herein, the compression information and the header information of the IRpacket may each be signaled to a different table (or section), as shownin FIG. 68, or may be signaled to the same table (or section), as shownin FIG. 70. If each of the compression information and the headerinformation of the IR packet is signaled to a different table (orsection), as shown in FIG. 68, at least one of a context profileinformation and a context identifier may be used as link information forconnecting the two different tables.

If the header compressing unit according to the present invention isapplied to the broadcasting transmitting apparatus shown in FIG. 11, theIP-PLP link information generating unit (700100) and the informationmerger (700200) may be separately provided, or the functions of theIP-PLP link information generating unit (700100) and the informationmerger (700200) may be performed by at least one of an IP servicecontroller (106020), an IP service information decoder (106030), an IPservice information correcting/generating module (106040), and an IPstream merger (106050). This may be identically applied in FIG. 72.Reference may be made to FIG. 11 for the parts that are not described inFIG. 72.

FIG. 73 illustrates a flow chart showing an input pre-processing methodincluding header compression according to the present invention.

More specifically, the IP service controller of the input pre-processor(100000) may set up (or determine) a UDP/IP filter (106010) based uponan IP address/port number, so that the data packets of the inputted IPstream can be filtered for each component, thereby being outputted(S701010).

At this point, the input pre-processor (100000) performs otheroperations in accordance with the component type of the data packet(S701020).

If the component type corresponds to IP service information, i.e., ifthe component type corresponds to common PLP data, the inputpre-processor (100000) may determine whether or not the IP service isrequired to be corrected (S701030). Then, when it is determined thatcorrection is required, the corresponding IP service information (ESGinformation, bootstrap information, provider information, and so on) isgenerated or corrected (S701040). Thereafter, by using an IP streammerger, diverse IP service information that are to be included in thedata, which are transmitted to the common PLP, are merged (S701060).

If the component type does not correspond to IP service information,i.e., if the component type corresponds to component PLP data, the inputpre-processor (100000) may set up (or determine) a physical PLPparameter based upon a component type, so that the determined physicalPLP parameter can be signaled to the L1/L2 signaling information(S701050). In other words, the input pre-processor (100000) may signalinformation on a component PLP structure to the L1/L2 signalinginformation, so that the receiver can process the component PLPcorresponding to the respective service in accordance with the componentstructure of the present invention.

Subsequently, the UDP/IP filter (106010) performs header compression byusing the RoHC compression method on the data packets, which arefiltered for each component (S701070). Herein, among the compressioninformation and the compressed data packets, the header information ofthe IR packet is signaled to at least one table (or section) beingtransmitted to the common PLP. At this point, IP-PLP mapping informationis also signaled along with the compression information. And, among thecompressed data packets, the header information of the IR_DYN packet,the FO packet, and the SO packet are respectively mapped to thecorresponding component PLP.

If the output data format corresponds to a GSE stream, GSE encapsulationmay be performs on the PLP data, which are processed in accordance withthe component type. If the data output format corresponds to an IPstream, this process step may be omitted.

The output of the input pre-processor (100000) is outputted to the inputprocessor (100100) (S701090).

Meanwhile, if the data packets having the respective header compressedby performing the above-described header compression procedure aretransmitted, after passing through the input processor (100100), theBICM module (100200), the frame builder (100300), and the OFDM generator(100400), the broadcasting signal receiving apparatus may perform headerdecompression based upon the IP-PLP mapping information, the compressioninformation, and so on, which are included in the L2 signalinginformation, the L2 signaling information being transmitted through theL1 signaling information, the common PLP, and so on.

If the broadcasting signal receiving apparatus is identical to thatshown in FIG. 26, the header decompression of the data packets isperformed by the output processor (138400). And, if the broadcastingsignal receiving apparatus is identical to that shown in FIG. 38, thedecompression of the data packets is performed at the outputting end ofthe BBF decoder (220600) or the outputting end of the buffer unit(220700).

At this point, among the compressed data packets, since the headerinformation of the IR packet are received by the common PLP, and sincethe header information of the remaining packets are received by thecorresponding component PLP, the header information of the IR packetshould be merged with the corresponding component PLP prior toperforming decompression on the data packets.

Whether or not the header of the data packets being transmitted to thecomponent PLP has been compressed may be known by using at least one ofthe L1 signaling information and the L2 signaling information. Forexample, whether or not the header of the data packets being transmittedto the corresponding component PLP may be verified based upon thePLP_PAYLOAD_TYPE field value of the L1 signaling information and/or theheader_compression_type field value of the L2 signaling information.

At this point, the component PLP, which is to be merged with the headerinformation of the IR packet, may be selected based upon the IP-PLPmapping information, which is signaled to the IP information table ofthe L2 signaling information. More specifically, an IP stream having anIP address/port number, which is signaled to thetarget_IP_address_descriptor( ), may be known by using the PLPinformation of the IP/MAC_location_descriptor( ), i.e., PLP profileinformation and PLP identifier, which is paired with thetarget_IP_address_descriptor( ).

Header information of the IR packet, which is received by the common PLPis merged with a component PLP, which is selected based upon the IP-PLPmapping information. Then, decompression is performed on the header ofthe data packets, which is included in the component PLP being mergedwith the header information of the IR packet, thereby recovering thedata packets to their initial states prior to being compressed. Thedecompression is performed based upon compression information, which issignaled to and received by the IP/MAC_location_descriptor( ) of thecommon PLP.

FIG. 74 shows an example of gaining header information of the IR packetfrom an IRT having the same value as the context profile information andcontext identifier of the IP information table, so as to merge thegained header information with the corresponding component PLP, when theIP-PLP mapping information and compression information are signaled toand received by the IP information table, and when the headerinformation of the IR packet is signaled to and received by the IRT.Herein, the component PLP is selected based upon the IP-PLP mappinginformation.

FIG. 75 shows an example of merging the header information of the IRpacket with the corresponding component PLP, when the IP-PLP mappinginformation, the compression information, and the header information ofthe IR packet are all signaled to and received by the IP informationtable. At this point, header information of the IR packet is notrequired to be additionally searched. Similarly, the component PLP isselected based upon the IP-PLP mapping information.

According to the embodiment of the present invention, the process ofmerging the header information of the IR packet, which is received bythe common PLP, to the corresponding component PLP is performed by adecompressing unit. Additionally, according to the embodiment of thepresent invention, the decompressing unit further includes an RoHCdecoder performing decompression on the data packets of the componentPLP, which is merged with the header information of the IR packet, byusing an inverse method of the RoHC compressing method.

FIG. 76 illustrates a block diagram showing the structure of thebroadcasting signal receiving apparatus according to yet anotherembodiment of the present invention, wherein a header decompressing unit(710090) is provided between a BBF decoder (710080) and a buffer unit(710100). More specifically, FIG. 76 corresponds to an exemplaryembodiment of the present invention respective to when a headercompressing unit of the broadcasting signal transmitting apparatus isprovided at the outputting end of the UDP/TP filter (106010). If theheader compressing unit is provided at the inputting end of the UDP/IPfilter (106010), the header decompressing unit (710090) is provided atthe outputting end of the buffer unit (710100).

Referring to FIG. 76, with the exception for an L2 scanning informationgenerating unit (710060) and a header decompressing unit (710090), theoperation processes of the remaining blocks are identical to those ofthe identical blocks included in the broadcasting signal receivingapparatus shown in FIG. 38. Therefore, detailed description of the samewill be omitted for simplicity.

The L2 scanning information generating unit (710060) extracts IP-PLPmapping information and compression information from the L2 signalinginformation, which is received by the common PLP, and then outputs theextracted information to the header decompressing unit (710090).Additionally, the L2 scanning information generating unit (710060)outputs the header information of the IR packet, which is received bythe common PLP, to the header decompressing unit (710090). For example,if the IP-PLP mapping information and the compression information aresignaled to and received by the IP information table, and if the headerinformation of the IR packet is signaled to and received by the IRT,header information of the IR packet is extracted from an IRT having thesame values as the context profile information and context identifier ofthe IP information table, thereby being outputted.

The header decompressing unit (710090) selects a component PLP that isto be merged with the header information of the IR packet based upon theinputted IP-PLP mapping information. Then, the header decompressing unit(710090) merges the header information of the IR packet to the selectedcomponent PLP. Thereafter, the header decompressing unit (710090)performs decompression on the header of each data packet included in thecomponent PLP, which is merged with the header information of the IRpacket, based upon the compression information, thereby recovering thedata packets to a state prior to being processed with compression.

Then, among the PSI/SI (IP service information) buffer, the bootstrapbuffer, the metadata buffer, the audio buffer, the video buffer, and thedata buffer of the buffer unit (710100), the PLP data that aredecompressed by the header decompressing unit (710090) are outputted toany one of the corresponding buffer via switching. Reference may be madeto the description of FIG. 38 for the processing of the PLP data,wherein header compression is not performed.

The description of the present invention will not be limited only to theabove-described exemplary embodiments of the present invention. And, asit is shown in the appended claims of the present invention, it will beapparent to those skilled in the art that various modifications andvariations can be made in the present invention, and that suchmodifications and variations cover the scope of the present invention.

Mode for Carrying out the Present Invention

As described above, the present invention is described with respect tothe best mode for carrying out the present invention.

INDUSTRIAL APPLICABILITY

As described above, the present invention may be fully (or entirely) orpartially applied to digital broadcasting systems.

What is claimed is:
 1. A method of processing broadcast data in atransmitter, the method comprising: generating service signalinginformation including service identification (ID) information andservice name information; generating Layer 2 (L2) signaling informationincluding mapping information between ID information for a PhysicalLayer Pipe (PLP) and an internet protocol (IP) address of a servicedescribed in the service signaling information; encoding, by a firstencoder, the L2 signaling information, service data and the servicesignaling information in Physical Layer Pipes (PLPs); interleaving by aninterleaver, the PLPs; encoding, by a second encoder, Layer 1 (L1)signaling information; constellation mapping, by a constellation mapper,the encoded L1 signaling information; mapping, by a frame builder, theconstellation mapped L1 signaling information and the interleaved PLPsinto a frame; modulating, by a modulator, data in the frame by anOrthogonal Frequency Division Multiplexing (OFDM) scheme; inserting, bya preamble inserter, a plurality of preamble symbols at a beginning ofthe frame after the modulating step, wherein at least one of thepreamble symbols is capable of being detected by a receiver at lowsignal levels; and transmitting, by a transmitter, a broadcast signalincluding the frame to the receiver through at least one transmissionantenna by using at least one radio frequency (RF) channel, wherein theL1 signaling information comprises first L1 signaling information andsecond L1 signaling information, wherein the first L1 signalinginformation includes size information of the second L1 signalinginformation, and wherein the second L1 signaling information includesencoding information of the PLPs.
 2. The method of claim 1, wherein thepreamble symbols includes a first preamble symbol and a second preamblesymbol, and wherein a postfix of the first symbol and a prefix of thesecond symbol are concatenated each other in the time domain.
 3. Themethod of claim 2, wherein the postfix of the first symbol carries afrequency shifted part of the first symbol and the prefix of the secondsymbol carries a frequency shifted part of the second symbol.
 4. Themethod of claim 3, wherein the postfix of the first symbol and theprefix of the second symbol are frequency shifted with same frequencyshift value.
 5. The method of claim 4, wherein the postfix of the firstsymbol and the prefix of the second symbol are frequency shifted withopposite signs, respectively.
 6. A transmitter for processing broadcastdata, the transmitter comprising: a signaling generator to generateservice signaling information including service identification (ID)information and service name information, wherein the signalinggenerator further generates Layer 2 (L2) signaling information includingmapping information between ID information for a Physical Layer Pipe(PLP) and an internet protocol (IP) address of a service described inthe service signaling information; a first encoder to encode the L2signaling information, service data and the service signalinginformation in Physical Layer Pipes (PLPs); an interleaver to interleavethe PLPs; a second encoder to encode Layer 1 (L1) signaling information;a constellation mapper to constellation map the encoded L1 signalinginformation; a frame builder to map the constellation mapped L1signaling information and the interleaved PLPs into a frame; a modulatorto modulate data in the frame by an Orthogonal Frequency DivisionMultiplexing (OFDM) scheme; a preamble inserter to insert a plurality ofpreamble symbols at a beginning of the frame after the modulating step,wherein at least one of the preamble symbols is capable of beingdetected by a receiver at low signal levels; and a transmitter totransmit a broadcast signal including the frame to the receiver throughat least one transmission antenna by using at least one radio frequency(RF) channel, wherein the L1 signaling information comprises first L1signaling information and second L1 signaling information, wherein thefirst L1 signaling information includes size information of the secondL1 signaling information, and wherein the second L1 signalinginformation includes encoding information of the PLPs.
 7. Thetransmitter of claim 6, wherein the preamble symbols includes a firstpreamble symbol and a second preamble symbol, and wherein a postfix ofthe first symbol and a prefix of the second symbol are concatenated eachother in the time domain.
 8. The transmitter of claim 7, wherein thepostfix of the first symbol carries a frequency shifted part of thefirst symbol and the prefix of the second symbol carries a frequencyshifted part of the second symbol.
 9. The transmitter of claim 8,wherein the postfix of the first symbol and the prefix of the secondsymbol are frequency shifted with same frequency shift value.
 10. Thetransmitter of claim 9, wherein the postfix of the first symbol and theprefix of the second symbol are frequency shifted with opposite signs,respectively.
 11. A receiver for processing broadcast data, the receivercomprising: a tuner to receive a broadcast signal including a frame byusing at least one reception antenna through at least one radiofrequency (RF) channel, wherein the frame includes Layer 1 (L1 )signaling information and Physical Layer Pipes (PLPs), wherein the PLPsincludes Layer 2 (L2) signaling information, service data and servicesignaling information, and wherein the service signaling informationincludes service identification (ID) information and service nameinformation; a preamble detector to detect a plurality of preamblesymbols at a beginning of the frame, wherein at least one of thepreamble symbols is capable of being detected at low signal levels; ademodulator to demodulate data in the frame by an Orthogonal FrequencyDivision Multiplexing (OFDM) scheme; a frame parser to parse the frameincluding the L1 signaling information and the PLPs; a constellationdemapper to constellation demap the L1 signaling information; a firstdecoder to decode the constellation demapped L1 signaling information; adeinterleaver to deinterleave the PLPs; and a second decoder to decodethe L2 signaling information, the service data and the service signalinginformation in the PLPs, wherein the L2 signaling information includesmapping information between ID information for a PLP and an internetprotocol (IP) address of a service described in the service information,and wherein the L1 signaling information comprises first L1 signalinginformation and second L1 signaling information, wherein the first L1signaling information includes size information of the second L1signaling information, and wherein the second L1 signaling informationincludes encoding information of the PLPs.
 12. A method of processingbroadcast data in a receiver, the method comprising: receiving abroadcast signal including a frame by using at least one receptionantenna through at least one radio frequency (RF) channel, wherein theframe includes Layer 1 (L1 ) signaling information and Physical LayerPipes (PLPs), wherein the PLPs includes Layer 2 (L2) signalinginformation, service data and service signaling information, and whereinthe service signaling information includes service identification (ID)information and service name information; detecting a plurality ofpreamble symbols at a beginning of the frame, wherein at least one ofthe preamble symbol is capable of being detected at low signal levels;demodulating data in the frame by an Orthogonal Frequency DivisionMultiplexing (OFDM) scheme; parsing the frame including the L1 signalinginformation and the PLPs; constellation demapping the L1 signalinginformation; decoding the constellation demapped L1 signalinginformation; deinterleaving the PLPs; and decoding the L2 signalinginformation, the service data and the service signaling information inthe PLPs, wherein the L2 signaling information includes mappinginformation between ID information for a PLP and an internet protocol(IP) address of a service described in the service information, andwherein the L1 signaling information comprises first L1 signalinginformation and second L1 signaling information, wherein the first L1signaling information includes size information of the second L1signaling information, and wherein the second L1 signaling informationincludes encoding information of the PLPs.